Sympathetic Innervation of Cerebral Arteries: Prejunctional Supersensitivity to Norepinephrine After Sympathectomy or Cocaine Treatment

Sympathetic innervation of cerebral arteries: prejunctional supersensitivity to norepinephrine after sympathectomy or cocaine treatment.

The inactivation of the norepinephrine transmitter in the region of the adrenergic receptor is one important function of the sympathetic nerve terminals innervating blood vessels. This capacity was tested on isolated cat's middle cerebral artery (MCA) by recordings of the contractile response induced by norepinephrine at various stages after sympathectomy (excision of the superior cervical gang...

Prejunctional and postjunctional actions of endogenous norepinephrine at the sympathetic neuroeffector junction in canine coronary arteries.

The effects of endogenous and of exogenous norepinephrine were studied in isolated rings of canine left circumflex coronary artery and its first ventricular branch. Norepinephrine was released from adrenergic nerve endings by transmural electrical stimulation and by tyramine. In rings contracted with prostaglandin F2 alpha, transmural electrical stimulation resulted in frequency-dependent relax...

Sensitization of Arteries, Veins, and Small Vessels to Norepinephrine after Cocaine.

Time course of the development of pre- and postjunctional supersensitivity in the rabbit ear artery after decentralization.

Changes in the sensitivity of the rabbit ear artery to exogenous norepinephrine and potassium and to sympathetic nerve electrical stimulation were examined in vitro following decentralization which was performed by removing the unilateral preganglionic nerve proximal to the superior cervical ganglion. The contralateral side was left intact as a control. The postjunctional supersensitivity to ex...

Modulation of norepinephrine release from sympathetic neurons of the rabbit aorta by prejunctional prostanoid receptors.

The pharmacological properties and subtypes of prostanoid receptors involved in the prejunctional modulation of [(3)H]norepinephrine release from sympathetic neurons were studied using isolated rabbit aorta. Rings preincubated with [(3)H]norepinephrine were washed with physiological salt solution that contained cocaine plus corticosterone, uptake(1) and uptake(2) inhibitors, respectively, and r...