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Wang XL, Lee TF, Wang LC. Do adenosine antagonists improve cold tolerance by reducing hypothalamic adenosine activity in rats? Brain Res Bull 1990; 24:389-93. [PMID: 2337820 DOI: 10.1016/0361-9230(90)90094-g] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Previously we have shown that systemic injection of adenosine antagonists can significantly improve cold tolerance in both rats and humans. However, it is not clear whether systemic administration of adenosine antagonist acts peripherally or centrally at the thermoregulatory site. To resolve this, theophylline (nonselective adenosine receptor blocker), cyclopentyltheophylline (selective A1 receptor blocker) or adenosine deaminase (an enzyme which inactivates adenosine by converting it into inosine) was injected directly into preoptic anterior hypothalamus (POAH) of rats and their thermogenic responses assessed. In contrast to that observed after systemic administration, intrahypothalamic injection of either adenosine antagonists or deaminase at various doses failed to elicit any enhancement in heat production beyond that of the controls. These results suggest that the beneficial effect of systemically injected adenosine antagonists in improving cold tolerance is not the result of altering the thermoregulatory functions mediated via the POAH.
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Affiliation(s)
- X L Wang
- Department of Zoology, University of Alberta, Edmonton, Canada
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2
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Alexander SJ, Cooper KE, Veale WL. Sodium salicylate: alternate mechanism of central antipyretic action in the rat. Pflugers Arch 1989; 413:451-5. [PMID: 2740200 DOI: 10.1007/bf00594172] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Infusion of sodium salicylate (50.0 or 100.0 micrograms/microliters) into the ventral septal area (VSA) of the rat brain suppressed Prostaglandin-E1-induced hyperthermia. Infusion of artificial cerebrospinal fluid (aCSF) or 10.0 micrograms doses of salicylate did not. The suppression of intracerebroventricularly-induced (icv) Prostaglandin E1 (PGE1) hyperthermia was not due to a hypothermic action of salicylate since salicylate infusions given during cold exposure (10.0 degrees C) did not lower core body temperatures. A possible interaction between salicylate and endogenous arginine vasopressin (AVP) was investigated. Infusion of both salicylate (50.0 micrograms/microliters) and either AVP antiserum or AVP antagonist into the VSA resulted in PGE hyperthermias occurring at levels which were not different from control levels as opposed to enhanced hyperthermia (antiserum or antagonist alone) or suppressed hyperthermia (salicylate alone). These results are consistent with the notion that sodium salicylate infusions within the VSA enhance AVP action and thus bring about the attenuation of PGE-induced hyperthermia.
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Affiliation(s)
- S J Alexander
- Department of Medical Physiology, Faculty of Medicine, University of Calgary, Alberta, Canada
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Alexander SJ, Cooper KE, Veale WL. Blockade of prostaglandin E1 hyperthermia by sodium salicylate given into the ventral septal area of the rat brain. J Physiol 1987; 384:223-31. [PMID: 3656145 PMCID: PMC1192259 DOI: 10.1113/jphysiol.1987.sp016451] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
1. Sodium salicylate (30.0 micrograms microliter-1) or artificial cerebrospinal fluid (ACSF) was infused bilaterally into the ventral septal area (v.s.a.) of the unrestrained rat for 1 h before and 1 h after the injection of prostaglandin E1 at a concentration of 20.0 ng microliter-1 into a lateral cerebral ventricle. 2. During control (ACSF) infusions, 200.0 ng of prostaglandin E1 evoked a hyperthermic response (0.95 +/- 0.16 degrees C). During sodium salicylate infusions, the prostaglandin E1-evoked hyperthermia was significantly reduced (P less than 0.025) to 0.31 +/- 0.16 degrees C. 3. The fever index (degrees C h for 1.0 h) during the infusion of sodium salicylate was reduced 66% below that of control infusions (P less than 0.01). 4. These data indicate that sodium salicylate infused in the v.s.a. of rats can antagonize a prostaglandin E-evoked hyperthermia. This suggests that there may be an additional mechanism of action for sodium salicylate antipyresis other than inhibition of prostaglandin E synthesis.
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Affiliation(s)
- S J Alexander
- Department of Medical Physiology, Faculty of Medicine, University of Calgary, Alberta, Canada
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Abstract
The N6-2'-O-dibutyryl derivative of adenosine 3',5'-monophosphate (db cyclic AMP) and related compounds have been micro-injected into the preoptic/anterior hypothalamic nuclei (PO/AH) of the unanaesthetized, restrained rabbit and the effects on deep body temperature observed. Db cyclic AMP (100-400 micrograms) produced hypothermia of rapid onset in rabbits at an ambient temperature of 20-23 degrees C. Hypothermia was also produced by N2-2'-O-dibutyryl guanosine 3',5'-monophosphate (db cyclic GMP), but not by saline, sodium n-butyrate, adenosine 3',5'-monophosphate (cyclic AMP), guanosine 3',5'-monophosphate, adenosine 5'-mono-, di- or triphosphate. The initial hypothermic response to db cyclic AMP and db cyclic GMP was followed by a sustained rise in temperature. However, all compounds injected into the PO/AH produced a similar hyperthermia which was attenuated by paracetamol. Development of this tissue-damage fever abolished the hypothermic response to db cyclic AMP in some rabbits. The effects of db cyclic AMP on body temperature and behaviour were not reproduced by the adenylate cyclase activators, cholera toxin (0.125-5 micrograms) and guanyl imidodiphosphate (5-400 micrograms). It is concluded that hypothermia is the principal effect of db cyclic AMP on body temperature when injected into the PO/AH in rabbits. These data do not support the proposal that endogenous cyclic AMP in the rabbit brain mediates pyrexia.
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Abstract
Purines are putative neurotransmitters which appear to be involved in regulating several vegetative functions. We examined the effect of purines and their antagonist, caffeine, on colonic temperature of rats. Adenosine injected ip lowered colonic temperature in a dose responsive manner at ambient room temperatures. Adenine and AMP also lowered body temperature whereas 7-methylinosine and inosine only slightly influenced colonic temperature. Caffeine (50 mg/kg) injected sc, increased colonic temperature and when injected within 60 seconds of adenosine, counteracted the hypothermic effect of adenosine (50 mg/kg). Low ambient temperature (4 degrees C) accentuated the thermoregulatory effects of adenosine. Thus adenosine appears to have a hypothermic effect on body temperature regulation when administered peripherally which can be reversed by caffeine.
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Kandasamy SB, Williams BA. Cholecystokinin-octapeptide-induced hyperthermia in guinea-pigs. EXPERIENTIA 1983; 39:1282-4. [PMID: 6315476 DOI: 10.1007/bf01990371] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Intracerebroventricular administration of cholecystokinin-octapeptide (CCK-8) at room temperature (21 degrees C) induced dose-related hyperthermia in guinea-pigs and also produced hyperthermia at low (10 degrees C) and high (30 degrees C) ambient temperatures. CCK-8-induced hyperthermia was direct and not mediated by prostaglandins, norepinephrine, cyclic AMP or naloxone-sensitive receptors.
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Kandasamy SB, Williams BA. Central effects of dibutyryl cyclic AMP and GMP on the temperature in conscious rabbits. Brain Res 1983; 277:311-20. [PMID: 6315145 DOI: 10.1016/0006-8993(83)90939-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Intracerebroventricular (i.c.v.) administration of dibutyryl cyclic AMP (Db-cAMP)- and dibutyryl cyclic GMP (Db-cGMP)-induced hyperthermia in rabbits. Central administration of 4-(3-cyclopentyloxy-4-methoxyphenyl)-2-pyrrolidone (ZK 62711), a selective inhibitor of cAMP phosphodiesterase, only accentuated the hyperthermia due to Db-cAMP whereas a selective inhibitor of cGMP phosphodiesterase, 2-O-proproxyphenyl-8-azapurin-6-one (M and B 22948), only potentiated the hyperthermia caused by Db-cGMP. The hyperthermia due to Db-cAMP and Db-cGMP was not mediated through prostaglandins (PG). In contrast, central administration of an alpha-adrenergic receptor antagonist, phenoxybenzamine, or a beta-adrenergic receptor antagonist, sotalol, only attenuated the hyperthermic response to Db-cAMP while a cholinergic muscarinic receptor antagonist, atropine, specifically antagonized Db-cGMP-induced hyperthermia. I.c.v. administration of a protein synthesis inhibitor, anisomycin, did inhibit the hyperthermia due to Db-cAMP and Db-cGMP. Opiate antagonist, naloxone, did not antagonize Db-cAMP- and Db-cGMP-induced hyperthermia. These results suggest that a protein mediator is implicated in the induction of hyperthermia by Db-cAMP and Db-cGMP and that cAMP and cGMP may be involved through alpha/beta-adrenergic and cholinergic muscarinic receptors respectively in the central regulation of heat production/conservation in rabbits.
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Kandasamy SB, Williams BA. Hyperthermic effects of centrally injected (D-ala2, N-Me-Phe4, Met-(O)5-ol)-enkephalin (FK 33-824) in rabbits and guinea-pigs. Neuropharmacology 1983; 22:1177-81. [PMID: 6316191 DOI: 10.1016/0028-3908(83)90077-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Intracerebroventricular administration of (D-ala2, N-Me-Phe4, Met-(O)5-ol)-enkephalin (FK 33-824) induced dose-related hyperthermia in rabbits and guinea-pigs. Prostaglandins (PG) and norepinephrine (NE) were not involved in the hyperthermia induced by FK 33-824 because a cyclooxygenase inhibitor, indomethacin, and an alpha-adrenoceptor antagonist, phenoxybenzamine, had no antagonistic effects. Likewise, cAMP was not required since a phosphodiesterase inhibitor, theophylline, did not accentuate the hyperthermia due to FK 33-824. It is suggested that mu receptors were involved in the induction of hyperthermia by FK 33-824 in rabbits and guinea-pigs since naloxone attenuated it. These results indicate that FK 33-824-induced hyperthermia is not mediated by PG, NE and cAMP, but rather that mu receptors are involved in the induction of hyperthermia by FK 33-824.
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Abstract
Intracerebroventricular administration of all three prototype non-peptide opioid receptor (mu, kappa and sigma) agonists, morphine, ketocyclazocine and N-allyl-normetazocine (SKF 10,047) induced hyperthermia in rabbits. Similar administration of peptide opioids like beta-endorphin (BE), methionine-enkephalin (ME) and its synthetic analogue D-ala2-methionine-enkephalinamide (DAME) also caused hyperthermia. As expected, the synthetic enkephalin DAME was more potent than the parent enkephalin. Of the three anion transport systems (iodide, hippurate and liver-like or L) present in the choroid plexus, it is suggested that only the L transport system seems to be important to ventricular inactivation of BE and DAME since iodipamide (an inhibitor of the L transport system) augmented the hyperthermia produced by BE and DAME. Prostaglandins (PG) and norepinephrine (NE) were not involved in peptide and non-peptide opioid-induced hyperthermia because a PG synthesis inhibitor, indomethacin, and an alpha-adrenergic receptor blocker, phenoxybenzamine, had no thermolytic effect on them. Likewise cAMP was not required since a phosphodiesterase inhibitor, theophylline, did not accentuate the hyperthermia due to peptide and non-peptide opioids. Naloxone-sensitive receptors were involved in the induction of hyperthermia by morphine. BE, ME and DAME since naloxone attentuated them. In contrast, the hyperthermic response to ketocyclazocine and SKF 10,047 were not antagonized by naloxone.
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Kandasamy SB, Williams BA. Opposing actions of dibutyryl cyclic AMP and GMP on temperature in conscious guinea-pigs. Neuropharmacology 1983; 22:65-70. [PMID: 6302546 DOI: 10.1016/0028-3908(83)90261-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Intracerebroventricular administration of dibutyryl cyclic AMP (Db-cAMP), induced hyperthermia in guinea-pigs which was not mediated through prostaglandins (PG) or norepinephrine since a prostaglandin synthesis inhibitor, indomethacin, and an alpha-adrenergic receptor blocking agent, phenoxybenzamine did not antagonize the hyperthermia. In contrast, the hyperthermic response to dibutyryl cyclic AMP was attenuated by central administration of a beta-adrenergic receptor antagonist, sotalol, indicating that cyclic AMP may be involved, through beta-adrenergic receptors, in the central regulation of heat production/conservation. Central administration of dibutyryl cyclic GMP (Db-cGMP) produced hypothermia which was not mediated via histamine H1- or H2-receptors and serotonin since the H1-receptor antagonist, mepyramine, the H2-receptor antagonist, cimetidine, and the serotonin antagonist, methysergide, had no antagonistic effects. The antagonism of hypothermia induced by dibutyryl cyclic GMP and acetylcholine + physostigmine, by central administration of a cholinergic muscarinic receptor antagonist, atropine, and not by a cholinergic nicotinic receptor antagonist, d-tubocurarine, suggests that cholinoceptive neurons and endogenous cyclic GMP may regulate heat loss through cholinergic muscarinic receptors. These results support a regulatory role in thermoregulation provided by a balance between opposing actions of cyclic AMP and cyclic GMP in guinea-pigs.
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Kandasamy SB, Williams BA. Prostacyclin-induced hyperthermia: implication of a protein mediator. Neuropharmacology 1982; 21:1065-72. [PMID: 6128689 DOI: 10.1016/0028-3908(82)90123-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Intracerebroventricular administration of prostacyclin (PGI2) at room temperature (21 degrees C) induced dose-related hyperthermia in rabbits and also produced hyperthermia at low (4 degrees C) and high (30 degrees C) ambient temperatures. The PGI2-induced hyperthermia was not mediated by its stable metabolite 6-keto prostaglandin F1 alpha. Of the three anion transport systems (iodide, hippurate and liver-like) present in the choroid plexus, only the liver transport system seems to be important to central inactivation of pyrogen, prostaglandin E2 (PGE2) and the PGI2. Iodipamide (an inhibitor of the liver transport system) augmented the hyperthermia produced by PGI2, PGE2 and pyrogen. Phenoxybenzamine and pimozide had no thermolytic effect on PGI2-induced hyperthermia. After norepinephrine (NE) and dopamine levels were depleted by 6-hydroxydopamine, PGI2 still induced hyperthermia. Indomethacin and SC-19220 (a PG antagonist) did not antagonize PGI2-induced hyperthermia. Furthermore, the hyperthermia due to PGI2 was not accentuated by theophylline. In contrast, the hyperthermic response to PGI2 was attenuated by central administration of the protein synthesis inhibitor, anisomycin. These results indicate that PGI2-induced hyperthermia is not mediated by NE, dopamine, PGS, cyclic AMP, but, rather, that a protein mediator is implicated in the induction of fever by PGI2.
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12
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Kandasamy SB, Kirlin WG, Kaul PN. Prostacyclin-induced hypothermia: involvement of central histamine H2-receptors. Life Sci 1981; 28:2553-60. [PMID: 7019618 DOI: 10.1016/0024-3205(81)90598-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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13
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Proceedings of the British Pharmacological Society. 16--18th December, 1980. Br J Pharmacol 1981; 73:175P-318P. [PMID: 7284696 PMCID: PMC2071855 DOI: 10.1111/j.1476-5381.1981.tb16787.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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14
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Clark WG, Clark YL. Changes in body temperature after administration of antipyretics, LSD, delta 9-THC, CNS depressants and stimulants, hormones, inorganic ions, gases, 2,4-DNP and miscellaneous agents. Neurosci Biobehav Rev 1981; 5:1-136. [PMID: 6112723 DOI: 10.1016/0149-7634(81)90039-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This survey concludes a series of complications of data from the literature, primarily published since 1965, on thermoregulatory effects of antipyretics in afebrile as well as in febrile subjects, LSD and other hallucinogens, cannabinoids, general CNS depressants, CNS stimulants including xanthines, hormones, inorganic ions, gases and fumes, 2,4-dinitrophenol and miscellaneous agents including capsaicin, cardiac glycosides, chemotherapeutic agents, cinchona alkaloids, cyclic nucleotides, cycloheximide, 2-deoxy-D-glucose, dimethylsulfoxide, insecticides, local anesthetics, poly I:poly C, spermidine and spermine, sugars, toxins and transport inhibitors. The information listed includes the species used, route of administration and dose of drug, the environmental temperature at which the experiments were performed, the number of tests, the direction and magnitude of body temperature change and remarks on the presence of special conditions such as age or lesions, or on the influence of other drugs, such as antagonists, on the response to the primary agents.
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Clark WG, Clark YL. Changes in body temperature after administration of acetylcholine, histamine, morphine, prostaglandins and related agents. Neurosci Biobehav Rev 1980; 4:175-240. [PMID: 6106915 DOI: 10.1016/0149-7634(80)90015-9] [Citation(s) in RCA: 102] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
This survey, the second in a series, presents extensive tabulations of literature, primarily since 1965, on thermoregulatory effects of cholinergic agonists and antagonists, histamine and H1- and H2-receptor antagonists, narcotic analgesics and antagonists in both non-tolerant and tolerant subjects and of prostaglandins and related agents. The information listed includes the species used, route of administration and dose of drug, the environmental temperature at which the experiments were performed, the number of tests, the direction and magnitude of body temperature change and remarks on the presence of special conditions, such as age or lesions, or on the influence of other drugs, such as antagonists, on the response to the primary drug.
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VEENENDAAL GH, NIJNANTEN FMAWOUTERSENVAN, DUIN CVAN, MIERT ASJPAMVAN. Role of circulating prostaglandins in the genesis of pyrogen (endotoxin)-induced ruminal stasis in conscious goats. J Vet Pharmacol Ther 1980. [DOI: 10.1111/j.1365-2885.1980.tb00409.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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18
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Fujimoto S, Tsushima H, Mori M. Antidiuretic and thermogenic effects of intracerebroventricular prostaglandin H2 in ethanol-anaesthetized rats. EXPERIENTIA 1980; 36:209-11. [PMID: 7371762 DOI: 10.1007/bf01953736] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
When PGH2 was administered intracerebroventricularly at doses of 5 and 15 nmoles in ethanol-anaesthetized rats, alcohol diuresis was inhibited and rectal temperature, blood pressure and heart rate were all significantly increased.
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Atkinson DC, Collier HO. Salicylates: molecular mechanism of therapeutic action. ADVANCES IN PHARMACOLOGY AND CHEMOTHERAPY 1980; 17:233-88. [PMID: 7004141 DOI: 10.1016/s1054-3589(08)60012-5] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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20
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Abstract
1. The antipyretic effects of corticosteroids on the fevers produced by bacterial and endogenous pyrogens in the rabbit were investigated. 2. Intravenous infusions of hydrocortisone and methyl prednisolone, when administered simultaneously with bacterial or endogenous pyrogens, failed to produce an antipyresis. 3. Pretreatment of rabbits with methyl prednisolone for 3 days diminished the febrile effect of both bacterial and endogenous pyrogens. 4. The fever produced by intrahypothalamic micro-injections of endogenous pyrogen was significantly attenuated by the simultaneous micro-injection of methyl prednisolone. 5. These results indicate that the antipyretic effect of steroids in the rabbit is the result not of a peripheral inhibition of endogenous pyrogen production, but rather of an action on the central nervous system.
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Shimomura K, Tomoi M, Mori J. The role of caudate nucleus dopamine and cyclic AMP in the hyperpyrexia induced by LiCl plus tranylcypromine in rats. JAPANESE JOURNAL OF PHARMACOLOGY 1979; 29:447-56. [PMID: 43914 DOI: 10.1254/jjp.29.447] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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PHARMACOLOGICAL ACTIVITY OF BACTERIAL PEPTIDOGLYCAN: THE EFFECT ON TEMPERATURE AND SLEEP IN THE RAT. Toxins (Basel) 1978. [DOI: 10.1016/b978-0-08-022640-8.50094-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] Open
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Isom GE, McCarthy TA, Eells JT, Wimer ER. Influence of intracerebroventricular injections of N6, O2'-dibutyryl adenosine 3':5'-cyclic monophosphate on sodium pentobarbital-induced narcosis in rats. Neuropharmacology 1978; 17:53-8. [PMID: 206854 DOI: 10.1016/0028-3908(78)90173-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abstract
The hyperthermic response to pyrogen was not potentiated by caffeine or theophylline administered i.p. into cats or rabbit. Injection of these drugs into the anterior hypothalamus or into the third cerebral ventricle in cats was also without effect on pyrexia. These results support the hypothesis that cyclic AMP in the anterior hypothalamus does not mediate pyrogen-induced hyperthermia in cats.
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Bito LZ. Inflammatory effects of endotoxin-like contaminants in commonly used protein preparations. Science 1977; 196:83-5. [PMID: 557238 DOI: 10.1126/science.557238] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Protein preparations from commercial suppliers are contaminated with bacterial endotoxins. The continued use of these preparations indicates that many researchers are unaware of this, and they may attribute all observed effects to the proteins themselves. Intravitreous injection of bovine serum albumin has an initial inflammatory effect on the rabbit eye which occurs before an immune reaction to the antigen itself can develop. This direct inflammatory effect can be fully accounted for by endotoxin-like contaminants which are present in protein preparations obtained from commercial suppliers. A pharmaceutical (U.S. Pharmacopeia) serum albumin preparation contains no detectable endotoxin, and has no initial inflammatory effect on the eye. Since endotoxins, even in minute amounts, have a variety of effects, the use of such contaminated protein preparations in biological research can lead to erroneous conclusions and should, therefore, be avoided.
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Willies GH, Woolf CJ, Rosendorff C. The effect of an inhibitor of adenylate cyclase on the development of pyrogen, prostaglandin and cyclic AMP fevers in the rabbit. Pflugers Arch 1976; 367:177-81. [PMID: 189286 DOI: 10.1007/bf00585155] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
An exotoxin of Bacillus thuringiensis known to inhibit adenylate cyclase in vitro has been used to investigate the role of cyclic AMP in the pathogenesis of fever in the rabbit. Intra-hypothalamic microinjections of the exotoxin are non-pyrogenic and significantly attenuate the hyperthermia caused by intrahypothalamic microinjections of both bacterial pyrogen (endotoxin) and prostaglandin E1. The hyperthermia produced by dibutyrl cyclic AMP is not affected by the exotoxin. These results support the idea that adenylate cyclase is activated during the development of fever in the rabbit.
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Woolf CJ, Willies GH, Rosendorff C. Does cyclic AMP have a role in the pathogenesis of fever in the rabbit? THE SCIENCE OF NATURE - NATURWISSENSCHAFTEN 1976; 63:94-5. [PMID: 180436 DOI: 10.1007/bf00622417] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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30
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Myers RD, Waller MB. Is prostaglandin fever mediated by the presynaptic release of hypothalamic 5-HT or norepinephrine? Brain Res Bull 1976; 1:47-56. [PMID: 824028 DOI: 10.1016/0361-9230(76)90048-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
An array of guide tubes to accommodate concentric push-pull cannulae was implanted chronically within the diencephalon of the rhesus or other species of macaque monkey which was accustomed to a primate chair. Colonic and skin temperatures were monitored continuously during each experiment in which a circumscribed site in the monkey's hypothalamus had been labelled by microinjection of 50-100 muCi serotonin (3H-5-HT) or 50-100 muCi or norepinephrine (3H-NE). Consecutive push-pull perfusions with an artificial CSF were carried out for 10 min at a rate of 50 mul/min at 20 min intervals. Under the control condition, a declining washout curve of radioactivity was obtained over 8-10 perfusions. Prostaglandin (PG) E1 in a concentration of 10-20 ng/min was added to the artificial CSF during the third and fifth successive perfusions. Nonlabelled PGE1 failed to exert a precise and consistent effect on the characteristic pattern of efflux of either tritiated 5-HT or NE from perfusion sites distributed widely throughout the hypothalamus and adjacent structures. However, in some experiments, an enhanced efflux of the indoleamine label did occur after the temperature had begun to rise following a perfusion with the PGE. In still other experiments, 15-20 muCi 3H-PGE1 was microinjected to label a perfusion site. Again the addition of either nonlabelled 5-HT or NE to the perfusion fluid produced an unreliable change or no alteration in the efflux of 3H-ge1 from sites in the anterior as well as other parts of the hypothalamus. These findings indicate that prostaglandin injected into the brain does not evoke hyperthemia by way of a pathological disturbance to the balance in the presynaptic release of 5-HT and NE within nerve endings in the rostral hypothalamus of the monkey. Conversely, neither 5-HT nor NE influences the prostaglandin activity within the hypothalamus, at least in so far as a functional change in the body temperature of the primate is concerned.
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31
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Willies GH, Woolf CJ, Rosendorff C. The effect of sodium salicylate on dibutyryl cyclic AMP fever in the conscious rabbit. Neuropharmacology 1976; 15:9-10. [PMID: 176610 DOI: 10.1016/0028-3908(76)90090-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Laburn H, Woolf CJ, Willies GH, Rosendorff C. Pyrogen and prostaglandin fever in the rabbit-II: Effects of noradrenaline depletion and adrenergic receptor blockade. Neuropharmacology 1975; 14:405-11. [PMID: 239366 DOI: 10.1016/0028-3908(75)90023-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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