Effects of alpha- and beta-adrenergic blockers on the actions of noradrenaline on body temperature in the newborn guinea-pig

1977 ◽  
Vol 33 (8) ◽  
pp. 1083-1084 ◽  
Author(s):  
Ibolya Komáromi
Keyword(s):  
Body Temperature ◽  
Guinea Pig ◽  
Beta Adrenergic ◽  
Adrenergic Blockers

CATECHOLAMINE ANTAGONISM TO OXYTOCIN-INDUCED MILK-EJECTION

1971 ◽  
Vol 68 (1_Suppla) ◽  
pp. S5-S38 ◽  
Author(s):  
Helmuth Vorherr
Keyword(s):  
Receptor Blockade ◽  
Milk Ejection ◽  
Beta Adrenergic ◽  
Beta Receptor ◽  
Beta Receptors ◽  
Alpha Receptors ◽  
Adrenergic Blockers ◽  
Beta Receptor Blockade ◽  
Second Pain ◽  
Stimulation Of

ABSTRACT In lactating rats and rabbits the mode of antagonism of sympathomimetics, angiotensin or pain toward oxytocin-induced milk-ejection was investigated. In rats intra-arterial (intrafemoral) doses of 0.01–0.02 μg or intravenous (iv) doses of 0.1–0.5 μg of either epinephrine, isoproterenol, norepinephrine, angiotensin or 10 μg of phenylephrine injected simultaneously with, or 30 seconds before an oxytocin dose (10 μU intrafemoral, 300 μU iv) greatly inhibited or suppressed the oxytocin response. A 15 second pain stimulus caused moderate inhibition. With alpha-receptor blockade pain, epinephrine, isoproterenol, norepinephrine, phenylephrine and angiotensin inhibition were, respectively, 70%, 75%, 100%, 40%, 0% and 100%. Under beta-receptor blockade the corresponding values were 14%, 40%, 0%, 70%, 100% and 100%; with simultaneous intrafemoral injections neither catecholamine was inhibitory toward oxytocin. In corresponding rabbit experiments approximately 10-fold higher iv drug dosages were applied and similar results were observed. In both species, combined alpha and beta-receptor blockade nearly eliminated the antagonistic actions of sympathomimetics toward oxytocin, whereas angiotensin inhibition persisted unchanged. The results indicate: 1) Mammary myoepithelial cells contain beta-adrenergic receptors but no alpha-receptors; 2) Inhibition of oxytocin-induced milk-ejection by isoproterenol and phenylephrine is meditated through stimulation of myoepithelial beta-receptors (myoepithelial relaxation) and vascular alpha-receptors (vasoconstriction), respectively; 3) Epinephrine and norepinephrine inhibition of milk-ejection is due to stimulation of vascular alpha-receptors and myoepithelial beta-receptors; 4) Angiotensin effects are unrelated to adrenergic receptor mechanisms; 5) Administration of both alpha and beta-adrenergic blockers is desirable for stabilizing the sensitivity of the oxytocin milk-ejection assay preparation against interference from endogenous or exogenous catecholamines; 6) Other than using adrenergic blockers, pharmacologic doses of oxytocin can correct nursing difficulties in animals and man with hyperfunction of the adrenal-sympathetic system.

Beta-Adrenergic Blockers for Chronic Heart Failure

2009 ◽  
Vol 17 (6) ◽  
pp. 287-292 ◽  
Author(s):  
Usman Javed ◽  
Prakash C. Deedwania
Keyword(s):  
Heart Failure ◽  
Chronic Heart Failure ◽  
Beta Adrenergic ◽  
Adrenergic Blockers

Beta-Adrenergic Blockers

2000 ◽  
pp. 120-147
Author(s):  
William H. Frishman ◽  
Angela Cheng-Lai ◽  
Julie Chen
Keyword(s):  
Beta Adrenergic ◽  
Adrenergic Blockers

scholarly journals Influence of New Ultrashort-Acting Beta-Adrenergic Blockers on Systolic Blood Pressure in Rats

2004 ◽  
Vol 73 (2) ◽  
pp. 181-185 ◽  
Author(s):  
M. Frydrych ◽  
L. Bartošová ◽  
T. Florian ◽  
J. Nečas ◽  
L. Bartošíková ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Systolic Blood Pressure ◽  
Beta Adrenergic ◽  
Adrenergic Blockers
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