We evaluated the distribution and ultrastructural characteristics of macrophages in the ovaries of women of reproductive ages, during pregnancy, and after menopause, by immunohistochemistry and transmission electron microscopy. Macrophages appeared around the ovarian follicle with its development. Their organelles were poorly developed, and no vacuoles or granules were observed in the cytoplasm. Macrophages were also present in the cavity of the atretic follicle, being larger in size than those in the developing follicle and characterized by cytoplasmic vacuoles and granules of a lysosomal nature. With the luteinization of the follicle, macrophages were seen to be distributed inside and outside the corpus luteum, but constituted only a minor population as compared with other kinds of leukocytes. The intracellular organelles were well-developed, including the lysosomal granules. In early pregnancy, the number of macrophages was noticeably increased in the corpus luteum. They were observed mainly outside the corpus luteum, and stained strongly with hCG immunohistochemically. Macrophages were present in the regressing corpus luteum and in the corpus albicans. Numerous lipid droplets and elongated cholesterol crystals were seen in the cytoplasm. Macrophages therefore appeared to be present throughout the ovarian cycle and may be involved in the development and atresia of the follicles and the progression and the regression of luteal tissues.
In this study, the changes in interleukin-1β (IL-1β) mRNA expression and its localization in the ovary were studied in pregnant mares' serum gonadotropin (PMSG)-human CG (hCG) injected immature rats. Moreover, to study the in vivo role of IL-1 during ovulation, the IL-1 receptor antagonist (IL-1ra) was injected into the bilateral bursae (100μg/15μl/bursa) immediately or at the 3rd, 5th, 10th h after hCG injection. IL-1β mRNA expression in the ovary had significantly (P<0.05) increased at the 6th h after hCG injection, and its level depended on the time interval between PMSG and hCG injections; the maximal IL-1β mRNA expression was observed when hCG was injected 48h after the PMSG injection. The signals of IL-1β mRNA localized in the thecal layer, particularly in the large preovulatory follicles. Intrabursal IL-1ra injection at the 3rd h after hCG injection showed a trend toward lowering the number of ova shed, and the injection at the 5th h significantly (P<0.01) decreased the number of ova shed compared with the saline injected control group. At the 24th h after hCG injection, there were a few large preovulatory follicles with distinguishable theca and granulosa layers in the IL-1ra treated ovary, although these two layers were indistinguishable in the control ovary. These results indicated that IL-β mRNA expression was definitely induced by hCG stimulation, and, moreover, this expression was dependent on the stage of follicular maturation. IL-1 may be important for the ovulation in the superovulatory cycle by PMSG in rats.
A 45-year-old woman with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) had muscular atrophy, severe cerebral and cerebellar atrophy, and cardiac hypertrophy. She also had diabetes mellitus treated with insulin, and sensorineural hearing loss. Ragged-red fibers were observed on muscle biopsy and an adenine to guanine transition mutation at position 3243 of her mitochondrial DNA was confirmed. Further investigations revealed that she also had hypothalamo-pituitary dysfunction. It appears that diabetes mellitus, hypothalamo-pituitary dysfunction, and the other abnormalities are all associated with mitochondrial dysfunction in this patient
Effects of bovine and human growth hormone-releasing hormone (GRF) analogs (bGRF(1-29)-NH2: bGRF-29, [D-Ala2, Ala15]-bGRF-29, [D-Ala2]-hGRF(1-29)-NH2: [D-Ala2]-hGRF-29), bovine GRF (bGRF(1-44)-NH2: bGRF-44), as well as rat GRF (rGRF) on GH release were studied in female calves. Intravenous (iv) bolus injections of 0.25μg/kg BW of bGRF-29, [D-Ala2, Ala15]-bGRF-29, and [D-Ala2]-hGRF-29 stimulated GH release. Plasma GH levels began to rise 10min after the injection of each peptide, and significant increases in GH concentrations were obtained at 60, 180 and 150min after the injection of bGRF-29, [D-Ala2, Ala15]-bGRF-29 and [D-Ala2]-hGRF-29, respectively. The concentrations of GH 80min after the injection of [D-Ala2, Ala15]-bGRF-29 were significantly higher than those after the injection of [D-Ala2]-hGRF-29 (except at 80 and 90min) or bGRF-29. The iv bolus injections of 0.25μg/ kg BW of bGRF-44 and rGRF stimulated GH release, and the GH-releasing potency of rGRF was approximately equal to that of bGRF-44. The plasma GH responses to the repeated iv injection of bGRF-29 or [D-Ala2, Ala15]-bGRF-29 at 2-h intervals were examined. bGRF-29 acutely increased plasma GH levels after each injection, and the high GH levels decreased to the basal values within 2h. In contrast, high GH levels induced by [D-Ala2, Ala15]-bGRF-29 were gradually decreased but not lowered to basal values throughout the experiment. These results show that [D-Ala2, Ala15]-bGRF-29 has longer-lasting and greater GH-releasing activity than the other GRF analogs in female calves, and the GH-releasing potency of rat GRF is approximately equal to that of bovine GRF in cattle in vivo
The present study was designed to characterize bihormonal cells in rat pituitary cells which secrete PRL and gonadotropins. This was done by using sandwich cell immunoblot assay (CIBA) and reverse hemolytic plaque assay (RHPA) in combination with immunocytochemistry (ICC) and by measuring the intracellular free calcium concentration ([Ca2+]i). The result of the experiment with sandwich CIBA revealed that the populations of LH- and FSH-secreting cells in the PRL-secreting cells were 6.23% and 5.91%, respectively, and the populations of the PRL secreting cells in the LH- and FSH-secreting cells were 18.4% and 15.5%, respectively. Additional studies by the combined techniques of RHPA with ICC revealed that the populations of LH- and FSH-containing cells in the PRL secreting cells were 4.43% and 2.40%, respectively, which were consistent with the results of Sandwich CIBA. Some of the PRL-secreting cells determined by RHPA showed responsiveness to TRH and GnRH in [Ca2+]i. These results suggest that bihormonal cells which secrete both PRL and LH, or both PRL and FSH are present in the normal rat pituitaries.
Although the inhibitory effects of a chronic excess of glucocorticoids (GC) on body growth and GH secretion are well established, the mechanisms involved remain unclear. In this study, we examined the chronic effects of a high dose of dexamethasone (DEX) on spontaneous GH secretion and insulin-like growth factor (IGF)-I in conscious rats. The animals were given daily ip injections of DEX (200μg/day) for either one or four weeks. Body growth assessed by tibia length and serum IGF-I levels was significantly inhibited 1 week after treatment. By contrast, spontaneous GH secretion was not altered 1 week after the treatment. Neither hypothalamic GRH and somtatostain mRNA levels nor GH responses to GRH from single somatotropes were affected 1 week after the treatment. Four weeks after DEX treatment, body growth of the rats was noticeably suppressed. Interestingly, spontaneous GH secretion, hypothalamic GRH mRNA levels and GH responses to GRH were all inhibited 4 weeks after treatment. Pituitary GRH receptor mRNA levels were not altered 1 week after treatment, but increased after 4 weeks. These results indicate that a high dose of DEX initially impairs IGF-I production and subsequently inhibits spontaneous GH secretion in rats. Inhibition of spontaneous GH secretion resulting from chronic GC excess is due, at least in part, to the impairment of hypothalamic GRH synthesis and pituitary GH responsiveness. An increase in the pituitary GRH receptor may be caused by decreased GRH secretion.
Thyroid-stimulating hormone (TSH) β subunit cDNA was obtained from Japanese quail (Coturnix japonica) by PCR and its nucleotide sequence was determined. The cDNA encodes a putative signal peptide and a mature protein consisting of 20 and 114 amino acids, respectively. The amino acid sequence of quail TSHβ subunit shows homologies of 67-69% in mammalian species, 58% in amphibian and 43-49% in teleost fish. Comparison of the amino acid sequence with TSHβ subunits of other species reveals some differences in several regions responsible for its biological functions and characteristic features of the avian TSHβ subunit, suggesting that the functional domains have diverged cooperatively between the hormone and its receptor during evolution.
Multiple endocrine neoplasia type 1(MEN 1) is rarely reported in Japanese and other oriental populations. To examine if there is a racial difference in the prevalence of MEN 1, we initiated extensive work on patients with endocrine tumors for additional lesions, and annual screening of family members of affected patients. In a four-year study, eleven asymptomatic patients were found by family screening, and the number of patients with MEN 1 in our clinics increased from 16 to 38. Estimated prevalence of MEN 1 was no less than 0.018/1000. MEN 1 may not be as rare as had been thought in Japanese, and the prevalence of MEN 1 in Japanese would not be significantly different from that of Caucasians. Systemic surveillance and extensive screening of family members are required for early detection and management of patients.
This paper describes for the first time the presence of 3β-hydroxysteroid dehydrogenase (3β-HSD) activity in osteoblast-like cells and investigates its characteristics. 3β-HSD activity was detected by the formation of androstenedione from [3H]dehydroepiandrosterone (DHEA) in whole cell assays of human osteoblast-like cells, HOS and MG-63. The radiolabeled product, androstenedione, was purified by thin-layer chromatography and identified by recrystallization on admixture with authentic androstenedione to show constant specific activities. The apparent Michaelis constant (Km) for DHEA in HOS was found to be 9.9μM and that in MG-63 was 80.4μM. The expression of the 3μ-HSD messenger ribonucleic acid in HOS and MG-63 was demonstrated through a reverse transcription-polymerase chain reaction. The PCR products were confirmed by Southern blot analysis. The existence of 3β-HSD in osteoblast-like cells indicates that these cells convertΔ5 androgens into more biologically active Δ4 3-keto steroids. These results, together with the demonstration of other steroid converting enzyme systems, suggest that the osteoblast cells play an important role in facilitating hormonal action in bone tissue.
We report here on a patient who was diagnosed with follicular carcinoma in 1985, and who was treated with total thyroidectomy. Two years later, when metastasis was found in his neck lesion, lung, pelvis and right femur, the patient received 131I treatment. Six years after receiving 131I treatment, the patient presented with hyperthyroidism. Whole-body scan with 131I revealed functioning metastasis in his right femur and pelvis. There was no hot spot in the neck region, confirming that no thyroid tissue remained. Blood panels revealed an increase in both TSH binding inhibitory immunoglobulin (TBII. 36.2%; normal. -10-10%) and thyroid stimulating antibody (TSAb, 176%; normal, less than 145%). Treatment with antithyroid drugs, dexamethasone and radioisotope therapy rapidly resolved his hyperthyroidism. Thyrotoxicosis and positive TRAb occurred in the absence of thyroid tissue, and many years after the completion of Rl therapy. The overproduction of thyroid hormone can therefore only be attributed to some mechanism of activity in the metastatic tumor tissue.
This study was performed to investigate whether the blockade of cholinergic muscarinic and adrenergic pathways was involved in the GH-releasing effect of GH-releasing peptide-2 (GHRP-2) in ovariectomized ewes. Cholinergic muscarinic antagonist, atropine (0.2mg/kg, iv, 15min before GHRP-2 administration) blunted the GH secretion caused by GHRP-2 (12.5μg/kgBW). α-Adrenergic antagonist phentolamine (15μg/kgBW•min, infusion from -15 to 30min) did not affect the GH response to GHRP-2, and β-adrenergic antagonist propranolol (0.25mg/kgBW, iv, 15min before GHRP-2 administration) did not suppress the GHRP-2-induced GH release. These results showed that cholinergic muscarnic antagonist agent, atropine, exerts an inhibitory effect on GHRP-2-induced GH secretion in ovariectomized ewes.
Keratinocyte growth factor (KGF) is secreted from mesenchymal fibroblasts and has a mitogenic specificity for epithelial cells in a paracrine fashion. In order to clarify the biological significance of KGF in the human endometrium which undergoes dynamic changes under the influence of sex steroid hormone, we investigated the gene expressions of KGF and its receptor (KGF-R) in the human endometrium in various sex steroid hormone milieus and chorionic villi, by RT-PCR and Northern blot hybridization. The secretory phase endometrium had a KGF mRNA level 10-fold greater than that of the proliferative phase endometrium. Similarly abundant KGF mRNA was found in decidua and pseudopregnant endometrium compared with proliferative phase endometrium. The KGF-R mRNA was detected by RT-PCR in chorionic villi from early pregnancy. These results indicate that the gene for KGF expressed in the human endometrium is mainly regulated by progesterone and that KGF might have a role in the interaction between decidua and chorion in early pregnancy in man.
The effect of radiofrequency lesions in the median or dorsal raphe nucleus (MRL or DRL) on copulatory behavior was examined in sexually inexperienced male rats. Three weeks after castration and the brain surgery, all males were subcutaneously implanted with Silastic capsules containing testosterone. In the first behavioral test, the frequency of ejaculation in the MRL group was significantly higher than that in sham and DRL males, but mount and intromission were not. Seven days after the first test, the second test was carried out after treatments with 100mg/kg p-chlorophenylalanine (PCPA), a serotonin synthesis inhibitor, or saline daily for 4 days in MRL and DRL males. The frequencies of male sexual behavior in PCPA treated DRL males were higher than those in saline treated DRL males. In contrast, even after treatments with PCPA, male sexual activity in MRL males was comparable to those in saline treated MRL males. These results suggest that serotonergic neurons in the median raphe nucleus play an inhibitory role in the regulation of male sexual activity, especially ejaculation. Furthermore, it can be thought that PCPA acts on the median raphe neurons and facilitates ejaculatory behavior.
A 45-year-old woman was referred to our hospital because of discomfort in the cervical region. Laboratory findings revealed thyrotoxicosis with positive TSH receptor antibodies, but acute inflammatory data were absent. After three weeks the thyroid hormone levels spontaneously decreased to hypothyroid levels, and thyroidal radioactive iodine uptake (RAID) was below normal. A needle-biopsy specimen of the thyroid gland obtained two months later showed diffuse lymphocytic thyroiditis, and she was therefore diagnosed as having had painless thyroiditis. Two months after returning to euthyroidism, a second thyrotoxicosis developed. TSH receptor antibodies remained positive, but RAIU was slightly above normal, indicating Graves' hyperthyroidism. Treatment with antithyroidal drugs was commenced but was soon discontinued due to an allergic reaction. Although only β-adrenergic antagonist was administered for treating the thyrotoxicosis, thyroid function was gradually normalized in parallel with the reduction in TSH receptor antibody. In this case, painless thyroiditis would be followed by Graves' disease and subsequent spontaneous remission.
We report a 47-year-old Japanese man who presented with visual disturbance due to a pituitary tumor with suprasellar extension. The patient had mild secondary hypothyroidism preoperatively, and was started on administration of levothyroxine sodium immediately before transsphenoidal surgery. After the operation, levothyroxine sodium was continued for several months. Pathological examination of the surgical specimen, together with endocrinological investigation revealed that the suprasellar tumor was a FSH-producing pituitary adenoma. Since 3 months after the operation, he has developed muscle weakness and finger tremor. He was found to be thyrotoxicosis, and levothyroxine sodium was discontinued. Seven weeks after levothyroxine sodium was discontinued, thyrotoxicosis continued, with a positive thyrotropin binding inhibitory immunoglobulin (TBII) and a high diffuse 123I-uptake by the thyroid. He was started on thiamazole 30mg/day. Although his thyroid dysfunction improved within 2 months, hyperthyroidism worsened repeatedly on attempts to discontinue thiamazole, and he required continuous treatment at 2.5mg/day. Patients with occult autoimmune thyroiditis rarely progress to thyrotoxicosis after operations on other endocrine organs such as the adrenal or parathyroid gland. In patients with pituitary adenoma, thyroid function and thyroid-associated autoantibodies should be investigated pre- and post-operatively.
Steroidogenic acute regulatory (StAR) protein plays a crucial role in the regulation of cholesterol transport from the outer mitochondrial membrane to the inner membrane, where P450scc participates in a rate-limiting step of adrenal steroidogenesis. We have already reported that both of cAMP- and protein kinase C-dependent processes may play a crucial role in the regulation of expression of StAR protein when bovine fasciculata cells are stimulated with ACTH. In the present study, ACTH increased cytosolic calcium movement and activated expression of StAR protein, resulting in enhancing cortisol production by bovine adrenal fasciculata cells. The role of the calcium/calmodulin-dependent protein kinase process in the regulation of expression of the StAR protein by ACTH was studied. The activating effects of ACTH on the StAR protein and cortisol production were inhibited by pretreatment with KN-93, a specific inhibitor of calcium/calmodulin-dependent protein kinase II. These findings suggest that ACTH can enhance expression of the StAR protein as well as cortisol synthesis in bovine adrenal fasciculata cells, in part via a calcium/calmodulin-dependent protein kinase process.