PURPOSE Studies have shown that the activation of adenosine A(1) receptors lower intraocular pressure primarily by increasing total outflow facility. The purpose of this study was to investigate the actions of the adenosine A(1) agonist N(6)-cyclohexyladenosine (CHA) on conventional outflow facility. METHODS Conventional outflow facility was evaluated in isolated bovine anterior segments, per...

PURPOSE Previous studies have shown that adenosine agonists are effective in reducing intraocular pressure (IOP). However, the mechanism(s) responsible for this ocular hypotensive effect has not been established. This study evaluates the relative contribution of changes in aqueous flow and outflow facility associated with the ocular hypotensive response to the adenosine agonist cyclohexyladenos...

introduction: considering the anticonvulsant effects of a1 adenosine receptors and the anatomical connections between pjriform cortex and amygdala, in this study, the role of a1 adenosine receptors activity of piriform cortex neurons on amygdala kindled seizures was investigated in rats. material and methods: the rats were fully kindled by daily electrical stimulation of amygdala. n6-cyclohexyl...

We used the patch-clamp technique to examine the effect of adenosine on epithelial sodium channel (ENaC) activity in rat cortical collecting duct (CCD). Application of adenosine inhibits ENaC activity, and the effect of adenosine was mimicked by cyclohexyladenosine (CHA), an A(1) adenosine-receptor agonist that reduced channel activity from 1.32 to 0.64. The inhibitory effect of CHA on ENaC was...

Renin is synthesized and released from juxtaglomerular (JG) cells. Adenosine inhibits renin release via an adenosine A1 receptor (A1R) calcium-mediated pathway. How this occurs is unknown. In cardiomyocytes, adenosine increases intracellular calcium via transient receptor potential canonical (TRPC) channels. We hypothesized that adenosine inhibits renin release via A1R activation, opening TRPC ...

We used the patch-clamp technique to study the effect of adenosine on the apical 70-pS K channel in the thick ascending limb (TAL) of the rat kidney. Application of 1 microM cyclohexyladenosine (CHA), an adenosine analog, stimulated apical 70-pS K channel activity and increased the product of channel open probability and channel number (NP(o)) from 0.34 to 0.7. Also, addition of CGS-21680, a sp...

Adenosine A1 receptors were characterized in membranes from rat dorsal and ventral spinal cord using [3H] cyclohexyladenosine [( 3H]CHA) and compared with those in brain. For determination of anatomical loci of adenosine A1 receptors in the dorsal and ventral spinal cord, various lesions were employed, including kainic acid injections directly into the lumbar dorsal spinal cord, spinal cord hem...

Guanine nucleotides, divalent cations, and sodium differentially regulate agonist and antagonist binding to adenosine A1 receptors in brain membranes. Guanine nucleotides decrease the binding of the adenosine A1 receptor agonist [3H]N6-cyclohexyladenosine ([3H]CHA) to guinea pig and bovine brain membranes by about 50% at 1--3 microM, while not affecting binding of the antagonist [3H]1,3-diethyl...

N6-Cyclohexyl[3H]adenosine ([3H]CHA) and 1,3-diethyl-8-[3H]phenylxanthine ([3H]DPX) to bind to adenosine receptors in brain membranes. The agonist [3H]CHA has high affinity in both bovine and guinea pig brain (Kd, 0.7 nM and 6 nM, respectively). [3H]CHA binding kinetics are slow (dissociation t1/2;60 min); binding is much higher at 25 degrees C than at 0 degrees C and is inhibited by guanine nu...

We used the patch-clamp technique to examine the effect of adenosine on the basolateral K channels in the thick ascending limb (TAL) of the rat kidney. A 50-pS inwardly rectifying K channel was detected in the basolateral membrane, and the channel activity was decreased by hyperpolarization. Application of adenosine (10 microM) increased the activity of basolateral 50 pS K channels, defined by ...