The facilitatory effect of tacrine was prevented by atropine and the Mantagonist pirenzepine, whereas the inhibitory effect induced by tacrine was blocked by atropine and the Mantagonist AF-DX 116. These results indicate that tacrine causes a biphasic effect on Kstimulated ACh release in the brain...
4. Both bicuculline-sensitive phases evoked by GABA and muscimol were abolished by tetrodotoxin or atropine, but were unaffected by guanethidine or naloxone. 5. The present results suggested that the biphasic GABA effect on the mechanical activity of the circular layer in cat terminal ileum was ...
Tacrine was found to biphasically both increase (10 -6 and 5 x 10 6 M) and decrease ( 1 0 - 5 - 1 0 -4 M) the release of ACh in a concentration-dependent manner. The facilitatory effect of tacrine was prevented by atropine and the M 1 antagonist pirenzepine, whereas the ...
Atropine (1 M ) decreased the twitch tension by 21±6% (n=7, p<0.05) without significant effects on the action potential and a Na i , and inhibited the effects of CCh. Cs + (20 m M ) increased the plateau height and APD 90 , enhanced the twitch tension by 66±24%, but ...
3 The effect of atropine, neurokinin-1 (NK_1) and neurokinin-2 (NK_2) receptor antagonists (SR140333 and SR48968, respectively) were tested to investigate the possible involvement of cholinergic and sensory nerve activation, respectively, in the response to IRL 1620. Likewise, the role of ...
Suramin abolished P2 of apnea. In awake rats, beta-citronellol induced biphasic hypotension and bradycardia being P1 abolished by methylatropine. In vitro, beta-citronellol inhibited spontaneous or electrically-evoked contractions of rat isolated right or left atrium, respectively, and fully relaxed ...
(by 76%) the second phase of bronchoconstriction but had no effect on the early component of the response.3The effect of atropine, neurokinin-1 (NK1) and neurokinin-2 (NK2) receptor antagonists (SR140333 and SR48968, respectively) were tested to investigate the possible involvement of ...
3 We discarded a direct effect of co-conotoxin GVIA (1 μM) plus tetrodotoxin (3.1 μM) or of atropine (1 μM) plus SP fragment 4-11 on smooth muscle cells because they did not modify caffeine responses in isolated tracheal myocytes. 4 We confirmed by HPLC that caffeine increased the...
3. Propranolol (10(-7) M) depressed the secondary phase by abolishing the biphasic pattern of the effect of HA leading it to a monophasic one (negative chronotropy). 4. On the other hand, combination with atropine (10(-7) M) was shown to reduce the negative inotropic effect (in the ...
Hirose M,Furukawa Y,Nagashima Y, et al.Pituitary adenylate cyclaseactivat- ing polypeptide-27 causes a biphasic chronotropic effect and atrial fibrillation in autonomically decentralized, anesthetized dogs.Journal of Pharmacology and Experimental Therapeutics. 1997...