OBJECTIVE To investigate the role of adrenoceptor subtypes in regulating the spontaneous contractile activity of the inner lining of the urinary bladder (urothelium/lamina propria). MATERIALS AND METHODS The responses of isolated strips of porcine urothelium/lamina propria to noradrenaline, phenylephrine, and isoprenaline were obtained in the absence and presence of receptor subtype-selective...

The 2 adrenoreceptor ( 2AR) is a prototypical G protein-coupled receptor (GPCR) activated by catecholamines. Agonist activation of GPCRs leads to sequential interactions with heterotrimeric G proteins, which activate cellular signaling cascades, and with GPCR kinases and arrestins, which attenuate GPCRmediated signaling. We used fluorescence spectroscopy to monitor catecholamine-induced conform...

Infant rat ultrasonic vocalizations (USVs) are widely believed to result from the induction of an emotional state of anxiety or distress. This perspective, however, is not easily reconciled with the demonstration by W. J. Farrell and J. R. Alberts 2000 that norepinephrine, a nonselective beta-adrenoceptor agonist with anxiogenic properties, inhibits production of USVs. Here, Farrell and Alberts...

This study was carried out to determine whether epinephrine alters the sensitivity of rat vagal sensory neurons. In anesthetized rats, inhalation of epinephrine aerosol (1 and 5 mg/ml, 3 min) induced an elevated baseline activity of pulmonary C fibers and enhanced their responses to lung inflation (20 cm H(2)O, 10 s) and right atrial injection of capsaicin (0.5 microg/kg). In isolated rat nodos...