In:
American Journal of Physiology-Endocrinology and Metabolism, American Physiological Society, Vol. 285, No. 1 ( 2003-07), p. E224-E231
Abstract:
Previous studies from our laboratory have demonstrated that administration of a myogenic plasmid that encodes a protease-resistant growth hormone-releasing hormone (HV-GHRH) to pregnant rat dams augmented long-term growth in first-generation progeny. In the present study, gilts were injected intra-muscularly at day 85 of gestation with 0, 0.1, 0.5, 1, or 5 mg of the HV-GHRH-expressing plasmid and were then electroporated. Piglets were weighed and bled periodically from birth to 100 kg. Piglets from gilts treated with 1 and 5 mg of HV-GHRH plasmid were larger at birth and weaning compared with controls. These two groups reached 100 kg 9 days earlier than the other groups. GHRH levels were increased at birth in piglets from treated gilts. IGF-I levels were significantly increased in the 5-mg group beginning at 21 days of age compared with controls. Pituitaries from the 5-mg group contained a significantly increased number of somatotrophs and lactotrophs from birth to 100 kg. This study confirms that enhanced maternal GHRH production results in intergenerational growth augmentation and that the magnitude of the response is dose dependent. The similarity of the response across species suggests that the effect is likely exerted as a fundamental component of gestational and developmental physiology.
Type of Medium:
Online Resource
ISSN:
0193-1849
,
1522-1555
DOI:
10.1152/ajpendo.00050.2003
Language:
English
Publisher:
American Physiological Society
Publication Date:
2003
detail.hit.zdb_id:
1477331-4
SSG:
12
Permalink