Pithed rats

Gibson, A., Wallace, P. Bern, H. A. (1986). Cardiovascular effects of urotensin II in anesthetized and pithed rats. Gen. Comp. Endocrinol. 64, 435-9. 

Denervated autonomic nervous system Denervated autonomic nervous system anesthetized pithed rat Collister and Osborn 107 AbdelRahman108... 

Wess J, Lambrecht G, Moser U, Mutschler E. (1987). Stimulation of ganglionic muscarinic Ml receptors by a series of tertiary arecaidine and isoarecaidine esters in the pithed rat. EurJ Pharmacol. 134(1) 61-67. 

Bums AT, Davies DR, McLaren AJ, Cerundolo L, Morris PJ, Fuggle SV (1998) Apoptosis in ischemia/reperfusion injury of human renal allografts. Transplantation 66(7) 872-876 Carruthers AM, Fozard JR (1993a) Adenosine A3 receptors mediate hypotension in the angiotensin II-supported circulation of the pithed rat. Br J Pharmacol 109(l) 3-5 Carruthers AM, Fozard JR (1993b) Effect of pertussis toxin treatment on the putative adenosine A i receptor-mediated hypotensive response in the rat. Eur J Pharmacol 250( 1) 185—188... 

Godlewski, G., Malinowska, B., Buczko, W., Schlicker, E., 1997a. Inhibitory H3 receptors on sympathetic nerves of the pithed rat activation by endogenous histamine and operation in spontaneously hypertensive rats. Naunyn-Schmiedeberg s Arch. Pharmacol. 355, 261-266. 

Malinowska, B., Schlicker, E., 1991. H3 receptor-mediated inhibition of the neurogenic vasopressor response in pithed rats. Eur. J. Pharmacol. 205, 307-310. 

Figure 8.4. Typical tracings of the blood pressure responses to bolus i.v. administration of ET-1 and big ET-1, both 1 nmoUkg, in the pithed rat. Adapted from Slee et al. [22 ].

The pressor response to big ET-1 can be used as the basis for an in vivo test for ECE inhibitors. In the pithed rat, an intravenous bolus dose (1 nmol/kg) of big ET-1, produces a marked and sustained rise in arterial pressure Figure 8.4) which can be inhibited in a dose-related manner by 1 minute pre-treatment with a bolus dose of phosphoramidon, 1-10 mg/kg i.v. Figure 8.5). 

Docherty JR, McGrath JC. Sympathomimetic effects of pancuronium bromide on the cardiovascular system of the pithed rat a comparison with the effects of drugs blocking the neuronal uptake of noradrenahne. Br J Pharmacol 1978 64(4) 589-99. 

Zhang EL, Chen X. Effects of ginsenosides on s)onpathetic neurotransmitter release in pithed rats. Acta Pharm Sinica 1987 8 217-220. 

It is worth mentioning that suramin and NF023 caused a blockade of vascular P2X purinoceptors after intravenous administration in the pithed rat [44,49]. In these in vivo... 

Effects of cannabinoids on the sympathetic nervous system have been studied in isolated tissues and in pithed animals (Table 4). Sympathetic neurons were usually activated by electrical stimulation. Activation of CBi receptors led to inhibition of noradrenaline and/or ATP release and, consequently, to inhibition of the effector responses in the heart, in mesenteric and renal blood vessels and in the vas deferens. Figure 5A shows that cannabinoids inhibit sympathetic neuroeffector transmission in the heart. Sympathetically mediated vasoconstriction was inhibited in many tissues of pithed rats and rabbits. Sympathetic tone is depressed during long-term A -tetrahydrocannabinol administration in humans the presynaptic inhibitory effect of cannabinoids on sympathetic axon endings maybe the basis of this effect. 

Malinowska B, Piszcz J, Koneczny B, Hryniewicz A, Schlicker E (2001) Modulation of the cardiac autonomic transmission of pithed rats by presynaptic opioid OP4 and cannabinoid CBi receptors. Naunyn-Schmiedeberg s Arch Pharmacol 364 233-241... 

Godlewski G, Malinowska B, Schlicker E (2004) Presynaptic cannabinoid CBl receptors are involved in the inhibition of the neurogenic vasopressor response during septic shock in pithed rats. Br J Pharmacol 142 701-708... 

Malinowska B, Godlewski G, Bucher B, Schlicker E (1997) Cannabinoid CBI receptor-mediated inhibition of the neurogenic vasopressor response in the pithed rat. Naunyn Schmiedebergs Arch Pharmacol 356 197-202... 

Figure 6 Effect of SR 120819A on the dose-response curve of NPY in pithed rats. Wistar rats were prepared as previously described (Serradeil-Le Gal etal., 1993). SR 120819A [100 (A), 300 ( ) pg kg-1 IV] or vehicle [control ( )] was injected 15 min before establishing the dose-response of NPY.

Similar conclusions could be derived from an investigation of antihypertensive clonidine analogs, with respect to their peripheral hypertensive side effects. For a series of clonidine-related imidazolines, log Papp values were determined in -octanol/buffer at pH 7.4, central antihypertensive activities C2s (molar doses that cause a 25% blood pressure decrease, intravenous application) in anesthesized rats, peripheral hypertensive activities C o (molar doses that cause a 60-mm Hg blood pressure increase, intravenous application) in pithed rats (i.e., rats without central nervous system control), binding affinities IC50ai to ai receptors (replacement of prazosin), and binding affinities IC50+ 10 a2 receptors (replacement of clonidine) [86,87],... 

Alkaloid Contraction of guinea pig ileum Pressor action in pithed rat Release of catecholamines from cat adrenal Contraction of frog rectus Blockade of contraction of diaphragm Inhibition of cat knee jerk Inhibition of cat flexor reflex Inhibition of chick flexor reflex Inhibition of chick crossed extensor reflex... 

Arecaidine propargyl, 2-butynyl and 2-pentynyl esters caused dose-dependent tachycardia in the pithed rat. This activity was blocked by small doses of pirenzepine, indicating that it was mediated by Mi ganglionic receptors. ... 

During activation of postganglionic sympathetic nerves there is an exocytotlc release of norepinephrine which is dependent upon the movement of calcium across the neural cell membrane. The effects of CEB on stimulus-secretion coupling in S3nnpathetlc nerves has been studied in several different preparations. Verapamil does not affect the neural release of norepinephrine in either Isolated cat heart or in the pithed rat. In the latter model nifedipine blunted increases in blood pressure due to activation of sympathetic nerves but did not affect cardiovascular responses to exogenous norepinephrine suggesting a prejunctional site of inhibition. 

Moya-Fluff FA, Maher TJ. 3-Adrenoceptor influences on the a - and 02-mediated vasoconstriction induced by phenylpropanolamine and its two component isomers in the pithed rat. J Pharm Pharmacol 1988 40 876-878. 

Roquebert J, DeMichel P 1984 Inhibition of the a-1- and a-2-adrenoceptor-mediated pressor response in pithed rats by raubasine, tetrahydroalstonine and akuammigine. Eur J Pharmacol 106 203-205... 

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