Human thyroid blood flow response to endogenous, exogenous human, and bovine thyrotrophin measured by electromagnetic flowmetry
Tegler, L.; Gillquist, J.; Anderberg, B.; Jacobson, G.; Lundström, B.; Roos, P.
Acta Endocrinologica 98(4): 540-548
1981
ISSN/ISBN: 0001-5598 PMID: 6458191 Document Number: 169140
Human thyroid blood flow (TBF) was studied with electromagnetic flowmetry during operation. Measurements were made of the effect on TBF of injections of bovine TSH into 1 inferior thyroid artery in 6 patients; 6 other patients were given human TSH, and in 10 patients measurements were made both of TBF and endogenous TSH released after administration of TRH in a peripheral vein. The TBF increased after all 3 types of injection. The mean of the TBF maxima after bovine TSH was 2.26 .+-. 0.35 (mean .+-. standard error of the mean) relative to basal TBF, after human TSH 1.97 .+-. 0.28 and after TRH 1.64 .+-. 0.20. In the 3 groups combined it was 1.92 .+-. 0.16. The TBF was often increased already during the 1st recording period 1-10 min after TSH or TRH administration. The mean TBF was approximately doubled at 30-50 min. There were considerable inter-individual variations in the latent time and maximum response of TBF, especially after human TSH, but no correlation was found between the response and the TSH serum concentration in any group. A prompt, but inter-individually varying, increase in TBF was confirmed. This increase is suggested to be secondary to an increased intrafollicular metabolic activity and not primarily regulating the thyroid function.