Detail of "71-82-9"

Reference

Iontophoretic application of opiates to the locus coeruleus

Iontophoretic application of opiates to the locus coeruleus. Bird, Stephanie J.; Kuhar, Michael J.In this study， 357-08-4 and 143-98-6 are also used. (Sch. Med., Johns Hopkins Univ., Baltimore, Md., USA). Brain Res., 122(3), 523-33 (English) 1977. CODEN: BRREAP. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacodynamics) The vast majority of morphine sulfate (I sulfate) [64-31-3]-sensitive single units in the area of the rat brain examd. were localized to the locus coeruleus. This corresponded well with the known distribution of the highest ds. of opiate receptor sites in this region of the midbrain. The effect of iontophoretically applied I was a marked and prolonged depression of spontaneous activity. Levorphanol tartrate [125-72-4], an opiate agonist, produced an effect similar to that of I while comparable doses of dextrorphan tartrate [143-98-6], it's clin. inactive stereoisomer, did not. Naloxone-HCl [357-08-4] and levallorphan tartrate [71-82-9] prevented as well as reversed the depression due to application of agonists. While the units were depressed following the application of opiate agonists, the cells were still excited by the neurotransmitter acetylcholine. Thus, neuronal sensitivity to opiates has a high pos. correlation with autoradiog. detd. opiate receptor sites, and this sensitivity to opiates is blocked by opiate antagonists and is stereospecific in nature. .

Influence of fentanyl on the chronotropic response of isolated rabbit atria to cholinergic and adrenergic stimulation

Influence of fentanyl on the chronotropic response of isolated rabbit atria to cholinergic and adrenergic stimulation. Hatano, Yoshio; Toda, Noboru (Fac. Med., Kyoto Univ., Kyoto, Japan). Jpn. J. Pharmacol., 28(1), 105-14 (English) 1978. CODEN: JJPAAZ. ISSN: 0021-5198. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacodynamics) The effects of fentanyl citrate (I citrate) [990-73-8] and morphine-HCl [52-26-6] on the chronotropic responses to transmural stimulation applied to the S-A node were studied in isolated rabbit atria. The stimulation caused a frequency-dependent neg. chronotropism followed by pos. chronotropism; the former was abolished by atropine and the latter suppressed by propranolol. The former response at 5 and 20/s was attenuated in a dose-dependent manner by I and morphine. The potency ratio of I to morphine was approx. 50-100. The inhibitory effect of I and morphine on the response to stimulation of cholinergic nerves was partially prevented or reversed by both naloxone [465-65-6] and levallorphan tartrate [71-82-9], and also partially reversed by repeated washing of the prepns. Antagonism by naloxone was appreciably greater than that of levallorphan. The neg. chronotropic response to transmural stimulation was reduced by levallorphan but not by naloxone. Dose-chronotropic response curves of acetylcholine were unaffected by treatment with I and morphine. High concns. of I and morphine attenuated the response to stimulation of adrenergic nerves, while dose-chronotropic response curves of noradrenaline were not influenced by these narcotics. Naloxone was ineffective in preventing or reversing the effect of I and morphine. Apparently, I and morphine activate opiate receptors located in cholinergic nerve terminals innervating the S-A node, thereby interfering with the release of acetylcholine. Further, it appears that high concns. of I and morphine interfere with the release of noradrenaline from postganglionic adrenergic nerve terminals in rabbit atria; however, this action is not related to opiate receptors.