Effect of alpha-2 adrenergic receptor stimulation on short-circuit current across isolated skin of the toad Bufo arenarum.
1. The effect of the alpha-2 adrenergic agonist clonidine on short-circuit current (SCC) across isolated skins of Bufo arenarum toads was investigated. 2. Clonidine inhibited basal SCC in a dose-dependent manner. 3. Blockade of the effect of clonidine on basal SCC by the selective alpha-2 antagonist yohimbine supports the hypothesis that the inhibitory effect is mediated by the stimulation of alpha-2 adrenergic receptors. 4. The fact that the inhibitory effect of clonidine is higher in skins with spontaneous positive SCC than in the negative ones, and that the alpha-2 agonist was unable to alter amiloride-induced negative SCC suggests that the inhibitory effect of clonidine may probably be mediated by inhibition of sodium transport.
Gamundi
S S
SS
Department of Physiology, INSIBIO (CONICET-UNT), San Miguel de Tucumán, Argentina.
Proto
M C
MC
Coviello
A
A
D000818:Animals; D002022:Bufo arenarum; D003000:Clonidine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004560:Electricity; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D011942:Receptors, Adrenergic, alpha / Q000502:physiology*; D012867:Skin / Q000187:drug effects; D012879:Skin Physiological Phenomena; D015016:Yohimbine / Q000494:pharmacology
D011942:Receptors, Adrenergic, alpha; D015016:Yohimbine; D003000:Clonidine