The relationship between calcium and increased sensitivity of rabbit aortae four hours after reserpine.
1 Four hours after reserpine, rabbit aortic strips were supersensitive to acetylcholine, isoprenaline and noradrenaline. The threshold concentration of the drugs necessary to induce a response was less and the maximum tension developed by the tissues was greater than in control strips. 2 Reserpine-treatment potentiated the contractile responses to CaCl2. 3 Reserpine-treatment resulted in an increase in calcium uptake and an increase in the slow component of 45Ca2+ efflux. 4 After resperine-treatment, the rate of relaxation from a potassium-induced contraction was decreased. 5 It is concluded that reserpine-induced supersensitivity is related to an enhanced ability of the tissue to retain and utilize calcium.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism*; D002122:Calcium Chloride / Q000494:pharmacology; D002132:Calcium Radioisotopes; D005260:Female; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D011817:Rabbits; D012110:Reserpine / Q000494:pharmacology*; D013997:Time Factors
D002132:Calcium Radioisotopes; D012110:Reserpine; D007545:Isoproterenol; D002122:Calcium Chloride; D000109:Acetylcholine; D002118:Calcium; D009638:Norepinephrine