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Horm Metab Res 2001; 33(3): 175-180
DOI: 10.1055/s-2001-14935
Original Clinical
© Georg Thieme Verlag Stuttgart · New York

Relaxin Causes Changes of the Liver. In Vivo Studies in Rats

D. Bani 1 , S. Nistri 1 , S. Quattrone 1 , M. Bigazzi 2 , T. Bani Sacchi 1
  • 1 Department of Anatomy, Histology and Forensic Medicine, Section of Histology, University of Florence, Florence, Italy
  • 2 Prosperius Institute, Florence, Italy
Further Information

Publication History

Publication Date:
31 December 2001 (online)

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During pregnancy, the liver undergoes metabolic adjustments directed to fulfil the needs of the mother and the growing fetus. This study was designed to verify whether relaxin, a hormone related to pregnancy, may induce histochemical and ultrastructural modifications of hepatocytes which can be related to metabolic changes. Estrogen-primed female rats were treated with relaxin (10 µg in repository vehicle) for 18 h. Additional male rats were treated with relaxin (10 µg/day in PBS) for 4 days. Appropriate vehicle-treated rats were used as controls. After fasting, the rats were killed and liver fragments were processed for light and electron microscopy and for computer-assisted morphometry of PAS-positive glycogen deposits and acid phosphatase-reactive organelles. In both sexes, the relaxin-treated rats underwent a significant decrease in the amount of glycogen in the hepatocytes as compared with the controls. These changes were accompanied by an increase in smooth endoplasmic reticulum, endocytosis vesicles and lysosomes. These findings show that relaxin promotes glycogen depletion and induces morphological changes of hepatocytes which are consistent with functional activation. It is suggested that relaxin might play an important role in hepatic metabolic adjustments occurring during pregnancy.

Key words:

Hepatocytes - Hormones of Pregnancy - Glycogen - Lysosomes - Ultrastructure

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Prof. Daniele  Bani

Dipartimento di Anatomia
Istologia e Medicina Legale
Sezione di Istologia

V. le G. Pieraccini, 6
50139 Firenze
Italy


Email: E-mail:bani@unifi.it.

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