[Changes of alpha1-adrenergic and muscarinic cholinergic responses of arterial blood pressure in the rabbit during adaptation to cold].
Changes in major parameters of alpha1-adrenergic and muscarinic cholinergic responses of arterial blood pressure (EC50 and P(m)) were studied in rabbits adapted to cold for 1-30 days (daily cold exposures for 6 hours at -10 degrees C). It was shown that responses to noradrenaline, adrenaline (agonists of alpha1-adrenoceptors) and acetylcholine (agonist of muscarinic cholinoreceptors) could be expressed by equation p = (Pm- A(n))/(EC50(n) + A(n)) with n = 1. Adaptation to cold induced radically different changes in the major parameters of adrenergic and cholinergic responses. In the noradrenergic responses, the parameters EC50 and Pm gradually decreased within 1-30 days of adaptation. In the adrenaline responses, Pm increased from 1 to 30 days of adaptation, EC50 decreased to 10 day and increased on the 30th day. In the muscarinic cholinergic response, the Pm value decreased from 1 and 10 days but returned to control values on the 30th day. IC5O did not differ from the control 1 day, decreased to 10 days and increased on the 30th day.
Manukhin
B N
BN
Anan'eva
O V
OV
Anan'ev
V N
VN
D000109:Acetylcholine / Q000494:pharmacology; D000222:Adaptation, Physiological; D058646:Adrenergic alpha-1 Receptor Agonists; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003080:Cold Temperature; D004837:Epinephrine / Q000494:pharmacology; D018721:Muscarinic Agonists / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D011817:Rabbits; D018340:Receptors, Adrenergic, alpha-1 / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000502:physiology*; D013997:Time Factors
D058646:Adrenergic alpha-1 Receptor Agonists; D018721:Muscarinic Agonists; D018340:Receptors, Adrenergic, alpha-1; D011976:Receptors, Muscarinic; D000109:Acetylcholine; D009638:Norepinephrine; D004837:Epinephrine