All issues
Volume 87 (1986)
- Issue 6 Pages 609-
- Issue 5 Pages 507-
- Issue 4 Pages 351-
- Issue 3 Pages 253-
- Issue 2 Pages 99-
- Issue 1 Pages 1-
Volume 87, Issue 6
Displaying 1-6 of 6 articles from this issue
- |<
- <
- 1
- >
- >|
-
Masaru NISHIKIBE, Masako SHIOYA, Akira NAKAJIMA, Jun NAGURA1986 Volume 87 Issue 6 Pages 609-618
Published: 1986
Released on J-STAGE: March 02, 2007
JOURNAL FREE ACCESSAntihypertensive action of TF-80, an α-tocopherylester of fusaric acid (FA), was studied in normotensive and hypertensive rats. Oral doses of TF-80 up to 100mg/kg did not affect systolic blood pressure in Wistar rats, whereas 50 and 100mg/kg doses produced a significant reduction in systolic blood pressure in both spontaneously hypertensive rats (SHR) and DOCA-salt hypertensive rats (DSR) without significant changes in heart rate. Although maximal reduction in systolic blood pressure at single oral dosing of TF-80 (50, 100mg/kg) and FA (15, 30mg/kg) was approximately the same extent, respectively, the antihypertensive action of TF-80 was longer-lasting than that of FA. TF-80 at a chronic administration of 1 to 100mg/kg/day for 6 ?? 9 weeks was preventive to the generation of hypertension in young SHR and DSR, but FA did not prevent the generation of hypertension. Hypotensive doses of TF-80 did not interfere in the rise in blood pressure produced by vasoactive substances such as norepinephrine, prostaglandin F2α and angiotensin II in SHR, and it also failed to inhibit plasma renin. TF-80 was also found not to have a diuretic effect. These results show that TF-80 has a mild and long-lasting antihypertensive action that is different from FA. However, the antihypertensive mechanism of TF-80 remains to be solved.View full abstractDownload PDF (7499K) -
(V). A comparison of eptazocine, pentazocine and morphine with regard to ability of tolerance development after successive administrationToshitaka NABESHIMA, Shigeyuki YAMADA, Tsutomu KAMEYAMA1986 Volume 87 Issue 6 Pages 619-627
Published: 1986
Released on J-STAGE: March 02, 2007
JOURNAL FREE ACCESSIt was investigated whether tolerance to the pharmacological actions and cross-tolerance between eptazocine and pentazocine/morphine were developed by successive administration of eptazocine. In the experiments of mice, successive administration of eptazocine failed to decrease the pharmacological actions of eptazocine on the acetic acid-induced writhing, the pressure and the wheel cage methods. Cross-tolerance between eptazocine and pentazocine/morphine was not observed. Tolerance to the actions of pentazocine and morphine was developed on the wheel cage and the acetic acid-induced writhing/pressure methods, respectively. Cross-tolerance between pentazocine and morphine was also developed on the pressure method. On the tail flick method of rats, tolerance to the action of eptazocine was observed, similar to morphine, but not cross-tolerance between eptazocine and morphine. These results suggest that there is species difference between mice and rats with regard to the ability of tolerance development and that the mechanisms of tolerance development between eptazocine and pentazocine/morphine may be different since eptazocine failed to show cross tolerance to these analgesics.View full abstractDownload PDF (6542K) -
Yoko AIDA, Yoko KANEKO, Toshio KASAMA1986 Volume 87 Issue 6 Pages 629-639
Published: 1986
Released on J-STAGE: March 02, 2007
JOURNAL FREE ACCESSEffects of oxybutynin hydrochloride on isolated smooth muscle were investigated in preparations of isolated rabbit bladder body, bladder base, collum vesicae and urethra. ACh produced a marked contraction of the preparation from the bladder body and produced no response in the collum vesicae and the urethra; however, NE caused a marked contraction of the preparations from the collum vesicae and the urethra and relaxation in the bladder body. Oxybutynin and papaverine hardly had any effect on these preparations. Effects of oxybutynin on the contractile response of the isolated ileum or urinary bladder of rabbit, guinea pig and rat in comparison with atropine, papaverine, flavoxate and other drugs were investigated. The responsibility of these preparations to ACh were approximately 100 times higher in the ileum than in the urinary bladder. Oxybutynin showed a competitive inhibition to contractile response induced by ACh in the ileum and urinary bladder, whose potency was about 1/7 ?? 1/10 that of atropine. In the ileum of rats which were treated with oxybutynin orally at a dose of 1, 10 or 100mg/kg for 60 days, the response to ACh in the preparations of the animals treated by 100mg/kg were decreased, but the anticholinergic action in the groups treated with oxybutynin were not significantly different compared with the nontreated or saline treated group. On the other hand, oxybutynin showed a non-competitive inhibition to contractile response induced by Ba2+, Ca2+ and histamine in the guinea pig ileum and Ba2+, high-K2+, Ca2+ and ATP in the rabbit urinary bladder. These potencies of oxybutynin were equal or slightly stronger than that of papaverine or flavoxate. However, oxybutynin had no effect on the contraction induced by NE in the rabbit urethra. The above results suggest that oxybutynin has atropine-like anticholinergic action and direct muscle relaxant action evidenced by noncompetitive inhibition to contractile response induced by several agonists.View full abstractDownload PDF (7170K) -
Junzo KAMEI, Tomokazu HOSOKAWA, Saizo YANAURA, Takehiko HUKUHARA1986 Volume 87 Issue 6 Pages 641-648
Published: 1986
Released on J-STAGE: March 02, 2007
JOURNAL FREE ACCESSEffects of naloxone on the cough depressant action of antitussive drugs were investigated in pentobarbital anesthetized male and female cats. Respiration and cough reflex were measured using a pneumotachograph via a cannula inserted into the trachea. The cough reflex was elicited by electrical stimuli to the superior laryngeal nerve. An i.v. administration of morphine (1mg/kg) significantly inhibited the cough reflex for at least 60 min. The antitussive effect of morphine was antagonized by naloxone (400 μg/kg). The inhibitory effect of morphine on the respiratory frequency was also antagonized by naloxone. The cough reflex was significantly inhibited by fominoben (5mg/kg, i.v.) and dextromethorphan (3mg/kg, i.v.). However, the respiratory frequency was increased by these two drugs. An i.v. administration of naloxone prevented the antitussive effects and the excitatory effects in respiratory frequency of fominoben and dextromethorphan. The present study suggests that the cough depressant actions of antitussive drugs may be mediated by endogenous opiates and/or by neurotransmitters which are modified by endogenous opiates.View full abstractDownload PDF (5038K) -
Masahiko TSUCHIYA, Shuji INOUE, Masayuki SATTA, Hideki YOSHIMURA, Masa ...1986 Volume 87 Issue 6 Pages 649-654
Published: 1986
Released on J-STAGE: March 02, 2007
JOURNAL FREE ACCESSEffect of an anorexiant, mazindol, on glucose absorption was investigated. Ten week-sold female Sprague-Dawley rats were divided into mazindol treated (fed on powder diet containing 100mg/kg of mazindol) and control groups. Four weeks later, experiments of 1) continuous observation of glucose absorption and 2) glucose transport were performed in each group using the everted sac method. During 180 min of continuous observation of glucose absorption, significantly lowered glucose concentrations of the serosal medium were observed in the mazindol treated group at oral and caudal ends of the upper, caudal end of the middle, and caudal ends of the lower small intestine, whereas no significant differences in glucose concentrations of the mucosal medium were observed between the two groups. After 60 min incubation for monitoring the glucose transport, significantly decreased glucose concentrations of serosal medium were observed in mazindol treated group at oral and caudal ends of the upper, caudal ends of the middle and caudal ends of the lower small intestine, whereas no significant differences in glucose concentrations of mucosal medium were observed. The results suggested that there is little effect on glucose absorption, but the metabolism of glucose or the remaining glucose in the small intestinal wall is increased by mazindol treatment.View full abstractDownload PDF (4122K) -
Satoru TANAKA, Makoto TANAKA, Akira AKASHI1986 Volume 87 Issue 6 Pages 655-663
Published: 1986
Released on J-STAGE: March 02, 2007
JOURNAL FREE ACCESSBudralazine was evaluated for its effect on the cerebral blood flow (CBF) in comparison with some antihypertensive drugs in spontaneously hypertensive rats (SHR). The oral doses for each drug were selected to reduce arterial blood pressure to near normotensive levels. Equihypotensive rats were also produced by a controlled-hemorrhage and used as a control group. The blood flows in the parietal cortex and caudate nucleus were measured using the hydrogen clearance method at the time points when the pressure levels averaged about 120 mmHg after administration of each of the drugs or controlled-hemorrhage. Budralazine (40mg/kg) significantly increased the regional CBF by approximately 60% with a significant decrease in the cerebral vascular resistance. A similar effect was also observed with hydralazine (9mg/kg). The CBF-increasing effect of nifedipine (7mg/kg) was less potent than that of budralazine. Neither prazosin (6mg/kg) nor α-methyldopa (1, 000mg/kg) increased the regional CBF. Such cerebrovascular responses were also observed with controlled-hemorrhage. Futhermore, budralazine given intravenously (3 ?? 10mg/kg) caused a significant and dose-dependent increase (50 ?? 250%) in the regional CBF without affecting the arterial blood pressure. This effect of budralazine was partially attenuated by the pretreatment with either reserpine or 6-hydroxydopamine. It is possible that catecholaminergic control of cerebrovascular tone is at least in part involved in the mechanism whereby budralazine increases the CBF.View full abstractDownload PDF (6575K)
- |<
- <
- 1
- >
- >|