Bombesin has both direct and indirect effects on pancreatic exocrine secretion in mammals. The latter is mediated through the release of cholecystokinin (CCK) . In rats, however, it is unclear whether bombesin's effects are direct or are mediated via release of CCK. This study was undertaken to determine the role of CCK in bombesin-stimulated pancreatic enzyme secretion in conscious rats. Pancreatic flow and protein output were increased significantly, two to three-fold over the basal secretion at 30 minutes after administration of 0.25 μg/kg/h and 0.5 μg/kg/h of bombesin in rats. Plasma CCK levels were not changed during that period in which pancreatic secretion was stimulated by bombesin. CR 1505, a CCK receptor antagonist, at 50 mg/kg, did not suppress pancreatic exocrine secretion stimulated by bombesin. It is concluded that the effect of bombesin on pancreatic secretion is a direct effect, and not mediated via release of CCK in rats.

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We studied the effects of the kampo medicines, sho-saiko-to (SST), oren-gedoku-to (OGT), sanmotsu-ogon-to (SOT), keigai-rengyo-to (KRT), senkyu-chacho-san (SCS), on rat hepatic drug-metabolizing enzymesin vivo. Hot-water extracts of each kampo medicine were given orally at doses of 100 and 1000 mg/kg. After a single administration, SST increased activities of aniline hydroxylase (ANH), aminopyrineN-demethylase (APD), and cytochrome c reductase (cyt. c red.) and levels of cytochromeP-450 (P-450) and cytochrome b₅ (b₅) in the liver. Single administrations of OGT, SOT, and SCS decreased activities of ANH and APD and P-450 content and increased cyt. c red. activity. A single administration of KRT at 100 mg/kg increased ANH and APD activities, but at a dose of 1000 mg/kg decreased both activities. Repeated administration of test drugs at doses of 100 and 1000 mg/kg/day for 14 days resulted in the following: SST and OGT reduced ANH activity; SCS and KRT reduced APD activity; OGT and KRT loweredP-450 content; cyt, c. red. activity was increased by SST, OGT, and SOT and was reduced by KRT. These results suggest that the examined kampo medicines may modify the effectiveness of simultaneously administered drugs that are metabolized by hepatic enzymes.

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This study compared cardiorespiratory responses and mechanical efficiency in the upper (UL) and lower (LL) limbs during repeated isokinetic extension-flexion exercise. Eight healthy male university students served as subjects. Each subject performed UL and LL exercises on separate days. The exercise consisted of three sets of maximal isokinetic extension-flexion actions at the elbow or the knee joints for 30 seconds at a speed of 180 degrees per second with a 30-second interval between sets. Heart rate (HR), oxygen uptake (Vo₂), carbon dioxide production (Vco₂), pulmonary ventilation (V_E), and respiratory rate (RR) were measured during and after exercise. From these measurements, tidal volume (V_T), ventilation equivalent (V_E/Vo₂), O₂pulse, net O₂requirement, and net mechanical efficiency were calculated. The volume of the upper arm and the thigh were determined with a water displacement method. The Vo₂, Vco₂, V_E, V_T, and HR during LL exercise were significantly higher (p<.05 to p<.001) than during UL exercise. The O₂pulse and V_E/Vo₂during UL exercise were significantly lower (p<0.01 and p<0.05) than during LL exercise. Limb volume was significantly (p<0.01 to p<0.001) correlated with Vo₂and mechanical efficiency. These results suggest that the lesser cardiorespiratory responses during UL exercise are related to the smaller muscle mass. Mechanical efficiency was also lower in UL exercise than during LL exercise. It seemed that not only the smaller muscle mass of the arm but also involvement of a greater static component and higher anaerobic metabolism during UL exercise contributed to the lower mechanical efficiency of UL exercise.

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The effects of the clofibrate derivatives fenofibrate (FF), bezafibrate (BF), and clinofibrate (CF), on hyperlipidemia induced by a cholesterol-free, high-fructose diet (HFD) in rats were investigated. Feeding of HFD for 2 weeks increased the high-density lipoprotein subfraction (HDL₁) and decreased the low-density lipoprotein (LDL) fraction. The levels of total cholesterol (TC), free cholesterol, triglyceride (TG), and phospholipid in serum were increased by HFD feeding. Administration of CF inhibited the increase in HDL₁content. All three agents inhibited the decrease in LDL level. Both BF and CF decreased VLDL level. Administration of FF, BF, or CF inhibited the increases of serum lipids, especially that of TC and TG. The inhibitory effects of CF on HFD-induced increases in HDL₁, TC, and TG were greater than those of FF and BF. These results demonstrate that FF, BF, and CF improve the intrinsic hyper-lipidemia induced by HFD feeding in rats.

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Catecholaminergic innervation of the rat neurohypophysis was studied by electron-microscopic immunocytochemistry for tyrosine hydroxylase using the preembedding peroxidase-antiperoxidase method. Examination of semithin sections of the neuro-intermediate lobe of the pituitary showed that most of the nerve fibers and terminals that displayed tyrosine hydroxylase (TH) -like immunoreactivity were in the parenchyma of the neurohypophysis, and that some of them were in close contact with pituicytes. Ultrastructurally, the TH-like immunoreactive (LI) terminals contained many small, clear vesicles and mitochondria in addition to some dense-core granules and large, clear vesicles. The reaction products were located around all of the membranous structures and within the dense-core granules. The TH-LI terminals were found to make synapse-like contacts with magnocellular neurosecretory fibers and terminals as well as with cell bodies and processes of pituicytes. At the sites of the synapse-like contacts, aggregations of small, clear vesicles in the presynaptic TH-LI terminal were seen. The present results provide ultrastructural evidence of catecholaminergic regulatory influence on some functions of magnocellular neurons and pituicytes in the neurohypophysis. The functional significance of the synapse-like contacts with special reference to neurosecretory hormone release in the neurohypophysis is discussed.

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Coagulation and fibrinolysis after hypophysectomy were studied in Wistar rats. Hypophysectomy by aspiration or sham-operation by the same procedure without touching the pituitary gland was performed on day 0. Various parameters of coagulation and fibrinolysis were examined on days 21 and 35. In rats that had undergone hypophysectomy, significant decreases in erythrocyte count, hematocrit, and hemoglobin concentration were observed on day 35 compared with those in sham-operated and control groups. The prolongation of r and k values and a decrease in ma value on thromboelastogram were observed on day 21, and r value was also prolonged on day 35. A significant decrease in fibrinogen level was observed on day 35 and an increase in the activity of factor XIII was found on days 21 and 35. Results of hepaplastin tests were lower on days 21 and 35. Antithrombin III activity and plasminogen level were higher on day 35. These results suggest that hypophysectomy suppresses coagulation and enhances fibrinolysis. These results also support the hypothesis that the pituitary gland influences the balance between blood coagulation and fibrinolysis.

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The effects of dietary consistency on body weight and the periodontium were studied in rat molars. Four-week-old rats in which the cellular cementum formation of the first molar had begun were divided into two groups and fed either a solid or a powdered diet for 5 weeks until the tooth roots were completed. At 9 weeks the body weight and periodontal morphology of the two groups were statistically analyzed with advancing age. The body weights of the powdered diet group were lower than those of the solid diet group. The periodontal ligament and cellular cementum on the distal surface of the distal root of the first molar was thinner in the powdered-diet group. These results suggest that dietary consistency can affect body weight and periodontal tissues in as little as 5 weeks.

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Dissociation of adrenal cortisol and androgen secretion occurs in elderly men and women. The postmenopausal ovary produces androgens; however, previous reports regarding adrenocortical function in postmenopausal women did not exclude the ovarian contribution to peripheral steroid levels. In the present study, changes in the ovarian contribution to adrenocortical function with age were determined by measuring peripheral concentrations of C₁₉ and C₂₁ steroids before and 2 weeks after ovariectomy. The rapid adrenocorticotropic hormone (ACTH) stimulation test (tetracosactide acetate, 0.25 mg i.v.) was performed, and the age-related difference in the response of steroid levels to ACTH stimulation was also determined in ovariectomized reproductive-age (mean age, 33.0 years, n=6) and postmenopausal women (mean age, 63.3 years, n=9) . After ovariectomy, the concentrations of pregnenolone, 17a-hydroxypregnenolone, progesterone, 17α-hydroxyprogesterone, dehydroepiandrosterone, and androstenedione in reproductive-age women decreased significantly to the levels in postmenopausal women. On the other hand, no significant changes in steroid levels before and after ovariectomy were observed in postmenopausal women. When changes in steroid levels in response to ACTH were compared, significant age-related reductions of dehydroepiandro-sterone, and androstenedione were observed with age but Δ4 and Δ5 C₂₁ steroid levels in response to ACTH were preserved. These results suggest that C_17-20 lyase activity decreases but 17a-hydroxylase is maintained for preservation of cortisol in response to ACTH. It is known that P450c17 is a single enzyme that catalyzes activity of both 17α-hydroxylase and C_17-20 lyase. Therefore, changes in adrenal C_17-20 lyase activity with age might affect adrenal androgen production.

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Percutaneous endoscopic gastrostomy (PEG) was performed on 15 patients who were completely dysphagic. The procedure was successful and well tolerated by all patients. Three patients still have a functioning PEG, the longest PEG lasting 20 weeks and the shortest lasting 4 weeks after insertion. In four patients in whom swallowing has recovered the tube has been removed 5 months after its insertion. Eight patients subsequently died of underlying disease, a mean of 110 days following PEG. Incisional infection occurred in only one patient and no other procedure-related complications occurred. In conclusion, PEG is a useful alternative to surgical gastrostomy in patients with dysphagia who have an anatomically normal esophagus.

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Slipped capital femoral epiphysis is uncommon among children in Japan. We studied 22 cases (26 hips) of this disease, in particular 8 cases (9 joints) treated with Imhauser's osteotomy. All patients were male and ranged in age from 12 to 19 years (mean, 13.9) . Onset was acute on chronic in one case and chronic in seven cases. The postoperative observation period ranged from 2 years 9 months to 13 years 3 months (mean, 5 years 10 months) . The results of Imhauser's osteotomy were satisfactory. Clinically, limp and pain disappeared, and Drehmann's sign became negative. The range of motion of the hip joint improved. The posterior tilting angle ranged from 31 to 60 degrees (mean, 39.9 degrees) before operation. The postoperative posterior tilting angle ranged from 5 to 30 degrees (mean, 13.7 degrees) . Aseptic necrosis of the femoral head did not develop, but chondrolysis developed in one patient after pin traction. For this patient, Imhauser's osteotomy was performed twice, after which the joint space widened and joint motion improved. However, shortening of the left leg occurred and an Ilizarov lengthening operation was performed. In some cases, the correction of slippage was insufficient. For cases with a high degree of slippage, subcapital osteotomy or Sugioka's rotational osteotomy is recommended.

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