Skip to main content
NCBI home page
British Journal of Pharmacology logoLink to British Journal of Pharmacology
. 1989 May;97(1):190–196. doi: 10.1111/j.1476-5381.1989.tb11941.x

TRH-induced blood flow and mean arterial pressure changes in the rabbit are not dependent on the anaesthetic used.

E E Hugoson-Seligsohn 1, L O Koskinen 1
PMCID: PMC1854490  PMID: 2497924

Abstract

1. The effects of thyrotropin releasing hormone (TRH) on regional cerebral blood flow were studied in rabbits anaesthetized with pentobarbitone or ketamine. The blood flow was determined with the labelled microsphere method before and after the i.v. administration of either 50 micrograms kg-1 or 2 mg kg-1 TRH. 2. In order to measure the cerebral O2 consumption the arteriovenous difference in oxygen saturation in the brain (CAVOD) was measured before and after the administration of 2 mg kg-1 TRH. 3. In animals under pentobarbitone anaesthesia 50 micrograms kg-1 TRH elicited an increase in mean arterial blood pressure (MAP) of about 1 kPa and 2 mg kg-1 TRH elevated the MAP by about 2 kPa. With ketamine as the anaesthetic the corresponding values were 0.5 kPa and 7 kPa, respectively. TRH induced significant vasoconstriction in several peripheral tissues. 4. The total cerebral blood flow (CBFtot) increased from 54 +/- 4 to 78 +/- 5 g min-1 100 g-1 after the administration of 50 micrograms kg-1 TRH in pentobarbitone-anaesthetized animals. An even greater effect was elicited by 2 mg kg-1 TRH, from 48 +/- 6 to 113 +/- 19 g min-1 100 g-1. In ketamine-anaesthetized rabbits, 50 micrograms kg-1 TRH tended to enhance the CBFtot and 2 mg kg-1 increased it from 71 +/- 6 to 141 +/- 19 g min-1 100 g-1. 5. In animals anaesthetized with pentobarbitone, the CAVOD decreased from 47.3 +/- 1.7% to 35.1 +/- 2.2% at 3 min after TRH delivery, and then gradually increased to the control level.(ABSTRACT TRUNCATED AT 250 WORDS)

Full text

PDF
190

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Alm A., Bill A. The oxygen supply to the retina. II. Effects of high intraocular pressure and of increased arterial carbon dioxide tension on uveal and retinal blood flow in cats. A study with radioactively labelled microspheres including flow determinations in brain and some other tissues. Acta Physiol Scand. 1972 Mar;84(3):306–319. doi: 10.1111/j.1748-1716.1972.tb05182.x. [DOI] [PubMed] [Google Scholar]
  2. Beale J. S., White R. P., Huang S. P. EEG and blood pressure effects of TRH in rabbits. Neuropharmacology. 1977 Jul-Aug;16(7-8):499–506. doi: 10.1016/0028-3908(77)90008-9. [DOI] [PubMed] [Google Scholar]
  3. Breese G. R., Cott J. M., Cooper B. R., Prange A. J., Jr, Lipton M. A., Plotnikoff N. P. Effects of thyrotropin-releasing hormone (TRH) on the actions of pentobarbital and other centrally acting drugs. J Pharmacol Exp Ther. 1975 Apr;193(1):11–22. [PMC free article] [PubMed] [Google Scholar]
  4. Breese G. R., Cott J. M., Cooper B. R., Prange A. J., Lipton M. A. Antagonism of ethanol narcosis by thyrotropin releasing hormone. Life Sci. 1974 Mar 16;14(6):1053–1063. doi: 10.1016/0024-3205(74)90230-6. [DOI] [PubMed] [Google Scholar]
  5. Burt D. R., Snyder S. H. Thyrotropin releasing hormone (TRH): apparent receptor binding in rat brain membranes. Brain Res. 1975 Aug 8;93(2):309–328. doi: 10.1016/0006-8993(75)90353-4. [DOI] [PubMed] [Google Scholar]
  6. Dhasmana K. M., Saxena P. R., Prakash O., Van der Zee H. T. A study on the influence of ketamine on systemic and regional haemodynamics in conscious rabbits. Arch Int Pharmacodyn Ther. 1984 Jun;269(2):323–334. [PubMed] [Google Scholar]
  7. GUILLEMIN R., YAMAZAKI E., GARD D. A., JUTISZ M., SAKIZ E. IN VITRO SECRETION OF THYROTROPIN (TSH): STIMULATION BY A HYPOTHALAMIC PEPTIDE (TRF). Endocrinology. 1963 Nov;73:564–572. doi: 10.1210/endo-73-5-564. [DOI] [PubMed] [Google Scholar]
  8. Grimm-Jorgensen Y., McKelvy J. F. Immunoreactive thyrotrophin releasing factor in gastropod circumoesophageal ganglia. Nature. 1975 Apr 17;254(5501):620–620. doi: 10.1038/254620a0. [DOI] [PubMed] [Google Scholar]
  9. Helke C. J., Phillips E. T. Thyrotropin-releasing hormone receptor activation in the spinal cord increases blood pressure and sympathetic tone to the vasculature and the adrenals. J Pharmacol Exp Ther. 1988 Apr;245(1):41–46. [PubMed] [Google Scholar]
  10. Horita A., Carino M. A., Lai H. Pharmacology of thyrotropin-releasing hormone. Annu Rev Pharmacol Toxicol. 1986;26:311–332. doi: 10.1146/annurev.pa.26.040186.001523. [DOI] [PubMed] [Google Scholar]
  11. Hökfelt T., Fuxe K., Johansson O., Jeffcoate S., White N. Distribution of thyrotropin-releasing hormone (TRH) in the central nervous system as revealed with immunohistochemistry. Eur J Pharmacol. 1975 Dec;34(2):389–392. doi: 10.1016/0014-2999(75)90269-1. [DOI] [PubMed] [Google Scholar]
  12. Inanami O., Meguro K., Ohno K., Sato A. Contribution of cholinergic vasodilators on the increase in cerebral cortical blood flow responses to the intravenous administration of thyrotropin releasing hormone in anesthetized rats. Neurosci Lett. 1988 May 26;88(2):184–188. doi: 10.1016/0304-3940(88)90123-1. [DOI] [PubMed] [Google Scholar]
  13. Jackson I. M., Reichlin S. Thyrotropin-releasing hormone (TRH): distribution in hypothalamic and extrahypothalamic brain tissues of mammalian and submammalian chordates. Endocrinology. 1974 Sep;95(3):854–862. doi: 10.1210/endo-95-3-854. [DOI] [PubMed] [Google Scholar]
  14. Koskinen L. D., Sperber G. O. Regional glucose metabolism in the rabbit brain in control and TRH-treated animals. Acta Physiol Scand. 1986 Mar;126(3):349–353. doi: 10.1111/j.1748-1716.1986.tb07826.x. [DOI] [PubMed] [Google Scholar]
  15. Koskinen L. O., Bill A. Thyrotropin-releasing hormone (TRH) causes sympathetic activation and cerebral vasodilation in the rabbit. Acta Physiol Scand. 1984 Oct;122(2):127–136. doi: 10.1111/j.1748-1716.1984.tb07490.x. [DOI] [PubMed] [Google Scholar]
  16. Koskinen L. O. Effect of low intravenous doses of TRH, acid-TRH and cyclo(His-Pro) on cerebral and peripheral blood flows. Br J Pharmacol. 1986 Mar;87(3):509–519. doi: 10.1111/j.1476-5381.1986.tb10193.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Koskinen L. O. Effects of TRH on cerebral and peripheral blood flows; role of submesencephalic brain stem centres. Acta Physiol Scand. 1986 Oct;128(2):277–288. doi: 10.1111/j.1748-1716.1986.tb07976.x. [DOI] [PubMed] [Google Scholar]
  18. Koskinen L. O. Effects of raised intracranial pressure on regional cerebral blood flow: a comparison of effects of naloxone and TRH on the microcirculation in partial cerebral ischaemia. Br J Pharmacol. 1985 Jun;85(2):489–497. doi: 10.1111/j.1476-5381.1985.tb08886.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Kraemer G. W., Mueller R., Breese G. R., Prange A. J., Lewis J. K., Morrison H., McKinney W. T., Jr Thyrotropin releasing hormone: antagonism of pentobarbital narcosis in the monkey. Pharmacol Biochem Behav. 1976 Jun;4(6):709–712. doi: 10.1016/0091-3057(76)90224-0. [DOI] [PubMed] [Google Scholar]
  20. Leppäluoto J., Koivusalo F., Kraama R. Thyrotropin-releasing factor: distribution in neural and gastrointestinal tissues. Acta Physiol Scand. 1978 Oct;104(2):175–179. doi: 10.1111/j.1748-1716.1978.tb06264.x. [DOI] [PubMed] [Google Scholar]
  21. Morley J. E. Extrahypothalamic thyrotropin releasing hormone (TRH) -- its distribution and its functions. Life Sci. 1979 Oct 29;25(18):1539–1550. doi: 10.1016/0024-3205(79)90435-1. [DOI] [PubMed] [Google Scholar]
  22. Morley J. E., Garvin T. J., Pekary A. E., Hershman J. M. Thyrotropin-releasing hormone in the gastrointestinal tract. Biochem Biophys Res Commun. 1977 Nov 7;79(1):314–318. doi: 10.1016/0006-291x(77)90097-3. [DOI] [PubMed] [Google Scholar]
  23. Oddsson L. Co-ordination of a simple voluntary multi-joint movement with postural demands: trunk extension in standing man. Acta Physiol Scand. 1988 Sep;134(1):109–118. doi: 10.1111/j.1748-1716.1988.tb08466.x. [DOI] [PubMed] [Google Scholar]
  24. Parker C. R., Jr, Capdevila A. Thyrotropin releasing hormone (TRH) binding sites in the adult human brain: localization and characterization. Peptides. 1984 Jul-Aug;5(4):701–706. doi: 10.1016/0196-9781(84)90010-x. [DOI] [PubMed] [Google Scholar]
  25. Schally A. V., Bowers C. Y., Redding T. W. Purification of thyrotropic hormone-releasing factor from bovine hypothalamus. Endocrinology. 1966 Apr;78(4):726–732. doi: 10.1210/endo-78-4-726. [DOI] [PubMed] [Google Scholar]
  26. Smith J. R., Carino M. A., Horita A. Interaction of various anesthetic agents with TRH: effects on temperature and arousal in rabbits. Proc West Pharmacol Soc. 1976;19:214–215. [PubMed] [Google Scholar]
  27. Taylor R. L., Burt D. R. Species differences in the brain regional distribution of receptor binding for thyrotropin-releasing hormone. J Neurochem. 1982 Jun;38(6):1649–1656. doi: 10.1111/j.1471-4159.1982.tb06646.x. [DOI] [PubMed] [Google Scholar]
  28. Wagner H. N., Jr, Rhodes B. A., Sasaki Y., Ryan J. P. Studies of the circulation with radioactive microspheres. Invest Radiol. 1969 Nov-Dec;4(6):374–386. doi: 10.1097/00004424-196911000-00004. [DOI] [PubMed] [Google Scholar]
  29. Yarbrough G. G. On the neuropharmacology of thyrotropin releasing hormone (TRH). Prog Neurobiol. 1979;12(3-4):291–312. doi: 10.1016/0301-0082(79)90012-1. [DOI] [PubMed] [Google Scholar]

Articles from British Journal of Pharmacology are provided here courtesy of The British Pharmacological Society

RESOURCES