In the urethane anesthetized spontaneously hypertensive rats (SHR) intraventricular injections of morphiceptin produced dose-related increase in heart rate and blood pressure. In contrary, intraventricular administration of morphiceptin in Wistar rats induced a fall in blood pressure and heart rate. Yohimbine antagonized pressor responses to morphiceptin in SHR. Naloxone counteracted both the stimulatory effects of morphiceptin in SHR as well as hypotensive responses in Wistar rats. Bilateral vagotomy blocked depressant action of morphiceptin in normotensive but failed to alter the pressor effects in SHR rats. After systemic injections of morphiceptin a fall in heart rate and blood pressure was obtained in both strains.

Analgesics↗

PubMedDate not supplied

Effect of aliphatic monoamines on motor activity of mice: no direct interaction with dopaminergic D2 receptor.

The effect of butylamine, pentylamine and hexylamine on spontaneous locomotor activity of mice was evaluated in the presence or absence of drugs affecting monoaminergic neurons. Pentylamine and hexylamine produced similar effects (stimulation after low, inhibition after high doses), while butylamine action was weak. Depression of locomotor activity produced by combined treatment with alpha-methyl-tyrosine, reserpine and dopa was counteracted by pentylamine and hexylamine; they did not produce such an effect in the absence of dopa. The amines did not displace 3H-spiperone specifically bound to striatal membranes.

Amines↗

PubMedDate not supplied

Analgesic activity and opiate receptor affinity of new derivatives of N-butylpiperidine.

The three newly synthesized derivatives of N-butylpiperidine 1-butyl-4-phenyl-4-isonicotinoylaminoethylpiperidine (BG 25), 1-buty-isonicotinoylpiperidine (BG 26) and N-(1-butyl-4-phenyl-4-piperidinoyl) tetrahydropapaverine (BG 9) were evaluated for analgesic activity and opiate receptor affinity. All the three compounds showed analgesic activity both in hot-plate and flinch-squeak-jump test in mice, BG 9 being the most potent. The affinity of the compounds to opiate receptor was moderate (in comparison with pentazocine): the affinity of BG 9 was much greater than that of BG 25 and BG 26. The compounds showed a pronounced inhibitory action in stimulated guinea-pig ileum preparation; this was reversible by naloxone. As evaluated on pA basis, all three investigated compounds showed moderate antagonistic activity. Also in this respect BG 9 was more active than the other two compounds. Cholinolytic and strong spasmolytic properties were observed in isolated rat ileum preparation for BG 9 only.

Analgesics↗

PubMedDate not supplied

The lack of affinity of prostaglandins to dopaminergic and opiate receptors in the rat striatum.

The aim of this paper was to study whether prostaglandins (PGs) E1, E2 and F2 alpha affect the binding of specific ligands for dopaminergic or opiate receptors 3H-spiroperidol or 3H-naloxone in the rat striatum. The PGs, even in very high concentrations, did not change 3H-spiroperidol or 3H-naloxone binding to rat striatal membranes in vitro. This indicates that in the striatum of rats PGs do not interact directly with dopaminergic and opiate receptors.

Animals↗

PubMedDate not supplied

[Huntington chorea - a generalized membrane defect?].

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Cell Membrane↗

PubMedDate not supplied

[Calcium antagonists and atherosclerosis].

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Animals↗

PubMedDate not supplied

Cold water stress induced analgesia in unilateral inflammation of the hindpaw in hypertensive and normotensive rats.

Analgesia induced by cold water stress (CWS) was tested in the model of monolateral inflammation in spontaneously hypertensive (SHR), renal hypertensive (RHR) and normotensive Wistar (NR) and Wistar Kyoto (WKY) rats. Unilateral hind paw inflammation was induced by Freund's complete adjuvant (FCA). Four days after inoculation all tested rats exhibited profound analgesia following CWS in both inflamed and non-inflamed paws which reached a maximum immediately after CWS and returned to control values within 15 min. The activity of naloxone was tested both by systemic and local injection. Baseline pain thresholds of SHR rats were significantly higher than those of NR, WKY and RHR. Hyperalgesia following systemic intraperitoneal administration of naloxone applied ten minutes before CWS was higher in RHR and WKY than in NR and SHR. When administered directly into the inflamed paw, naloxone did not antagonize CWS-induced analgesia in RHR, in contrast to weak antagonism in NR, while more evident in SHR and WKY. Our results probably reflect biological and genetic variability of intrinsic opioid and inflammatory mechanisms in hypertension.

Animals↗