+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Activation of 5-HT1A receptors in the paragigantocellularis lateralis decreases shivering during cooling in the conscious piglet

, : Activation of 5-HT1A receptors in the paragigantocellularis lateralis decreases shivering during cooling in the conscious piglet. American Journal of Physiology. Regulatory, Integrative and Comparative Physiology 293(1): R518-R527

Activation of 5-HT(1A) receptors in the medullary raphé decreases sympathetic outflow to thermoregulatory mechanisms, including brown adipose tissue (BAT), thermogenesis, and peripheral vasoconstriction when these mechanisms are previously activated with leptin, prostaglandins, or cooling. These same mechanisms are also inhibited during rapid eye movement (REM) sleep. It is not known whether shivering is also modulated by medullary raphé neurons. We previously showed in the conscious piglet that activation of 5-HT(1A) receptors with 8-OH-DPAT (DPAT) in the paragigantocellularis lateralis (PGCL), a medullary region lateral to the midline raphé that contains 5-HT neurons, decreases heart rate, body temperature and muscle activity during non-rapid eye movement (NREM) sleep. We therefore hypothesized that activation of 5-HT(1A) receptors in the PGCL would also attenuate shivering and peripheral vasoconstriction during cooling. During REM sleep in a cool environment, shivering, carbon dioxide production, and body temperature decreased, and ear capillary blood flow and ear skin temperature increased. Shivering associated with rapid cooling was attenuated after dialysis of DPAT into the PGCL. In animals maintained in a continuously cool environment, dialysis of DPAT into the PGCL attenuated shivering and decreased body temperature, but there were no significant increases in ear capillary blood flow or ear skin temperature. We conclude that both naturally occurring REM sleep and exogenous activation of 5-HT(1A) receptors in the PGCL are associated with a suspension of shivering during cooling. Our data are consistent with the hypothesis that 5-HT neurons in the PGCL facilitate oscillating spinal motor circuits involved in shivering but are less involved in modulating sympathetically mediated thermoregulatory mechanisms.


PMID: 17409258

DOI: 10.1152/ajpregu.00816.2006

Other references

Marland, A.; Sarkar, P.; Leavitt, R., 1999: The urinary elimination profiles of diazepam and its metabolites, nordiazepam, temazepam, and oxazepam, in the equine after a 10-mg intramuscular dose. A method for the extraction of diazepam and its metabolites (nordiazepam, temazepam, and oxazepam) from equine urine and serum and their quantitation and confirmation by liquid chromatography-tandem mass spectrometry is described. Valium, a formul...

Barnett, J.L.; Hemsworth, P.H.; Cronin, G.M.; Newman, E.A.; McCallum, T.H., 1991: Effects of design of individual cage-stalls on the behavioural and physiological responses related to the welfare of pregnant pigs. This experiment describes the effects of two designs of individual cage-stalls on the behavioral and physiological responses of pregnant pigs. There was a total of 32 experimental pigs housed in two designs of cage-stalls, vertical or horizontal b...

Chen, W.; Pedersen, M.; Gram-Nielsen, S.; Aasted, B., 1998: Production and characterization of monoclonal antibodies against mink leukocytes. Three monoclonal antibodies (mAbs) were generated against mink leukocytes. One antibody reacted with all T lymphocytes, one with all monocytes and one had platelet reactivity. Under reducing conditions, the T lymphocyte reactive antibody immunopre...

Lamina, J., 1974: Immunodiagnosis of visceral larva migrans in man. The microprecipitation test (MPT) with living Toxocara canis larvae and the gel precipitation test with adult Toxocara antigen revealed 73 positives in 707 sera from patients with suspected visceral larva migrans in Germany and adjacent countries....

Spitzer, S.G.; Pindur, G.; Gerk, U.; Jung, F., 2002: Influence of two non-ionic radiographic contrast media with different osmolalities on coagulation in invasive cardiology. A prospective, randomised comparative study. To investigate the influence of two non-ionic radiographic contrast media with different osmolality on thrombocytic function and the plasmatic coagulation system. The study was carried out as a randomised, prospective, comparative study with two c...

Inman, John W., 2000: Time for equipment planning. American Vegetable Grower 48(10

Gledhill, A.W., 1953: Some veterinary diseases of medical interest. British Medical Bulletin 9(3): 237-241

Warrick Jonathan A.; Orzech Kevin M., 2006: The effects of urbanization on discharge and suspended-sediment concentrations in a Southern California river. U S

Dolling, W.R., 1997: Two recent immigrants now found north of the Humber (Hym., Vespidae and Hem., Lygaeidae). Dolichovespula media and Nysius senecionis were found north of the Humber River, UK, in summer 1996 and summer 1997, respectively.

Piechocki, M.P.; Lonardo, F.; Ensley, J.F.; Nguyen, T.; Kim, H.; Yoo, G.H., 2002: Anticancer activity of docetaxel in murine salivary gland carcinoma. The purpose of this study was to evaluate the biological mechanisms of docetaxel (TXT) on salivary gland carcinoma. The effects of TXT on a spontaneous murine salivary carcinoma were determined. Proliferation, cell cycle regulation, connexin43 exp...