It has been well established that the antihypertensive drugs clonidine and methyldopa lower blood pressure by acting on postsynaptic alpha 2-adrenergic receptors within cardiovascular control centers of the brain. A number of novel agents designed as lipophilic and highly selective alpha 2-adrenergic stimulants have been synthesized and in general the pharmacological features of these agents re...

Prazosin, an antagonist of alpha 1-adrenergic receptors, has been found to suppress the clinical and histological expression of experimental autoimmune encephalomyelitis (EAE) in the Lewis rat. Suppression was more significant in females than in males and was a dose-dependent phenomenon. Analysis of the effect of other adrenergic receptor antagonists supports the conclusion that the suppressive...

Luteal cells are known to possess receptors for LH/hCG and receptors of the beta-adrenergic type. Interactions of specific agonists with either receptor lead to the activation of adenylate cyclase and subsequently to an increase of cAMP. Since in the human there is also evidence for the presence of alpha-adrenergic receptors, we have investigated whether activation of these receptors is linked ...

Uterine contractile activity in nonpregnant conscious dogs was investigated based on 2- to 6-mo-long continuous recording by means of a chronically implanted force transducer. We found that nonpregnant uterine contractile activity could be classified into six major patterns: sporadic contractions, weak and strong tonic contractions, weak and strong phasic contractions, and phasic contraction bu...

The "frontal aging hypothesis" has been proposed by many researchers suggesting that the earliest and most severe age-related changes in the cortex occur in the frontal lobes. Two of these changes include decreases in cognitive functions mediated by the prefrontal cortex (PFC) and significant decreases in norepinephrine (NE) and dopamine (DA). To investigate whether the changes in these neurotr...

The PNS was anticipated to be involved in the modulation of immune responses. To study aspects of this neuronal-immune communication, a recently developed tissue slice method was used to study the effects of adrenergic and opioidergic transmitters on interleukin 6 (IL-6) secretion in the spleen. The alpha 2-adrenergic agonist p-aminoclonidine (10(-7) M) inhibited IL-6 secretion (control vs. p-a...

KONDO, S., KAGAYA, M., TASHIMA, Y. and MORITA, T. The Quantitative Difference in Adrenergic Alpha-1, Alpha-2 and Beta Receptors between the Prostatic and Epididymal Ends of Dog Vas Deferens. Tohoku J. Exp. Med., 1992, 167 (2), 167-169 In order to study the regional differences in the distribution of adrenergic receptors of the vas deferens, we measured the amounts of adrenergic a-1, a-2 and R r...

noradrenaline release.8.9 While clonidine and the opiates have similar effects on the locus coeruleus, clonidine appears to exert specific effects through non-opiate, alpha-2 adrenergic receptors. 6, These data suggested that the opiate-withdrawal syndrome is due to increased noradrenergic neuronal activity in areas such as the locus coeruleus which are regulated both by alpha-2 adrenergic and ...