1989
DOI: 10.1530/acta.0.1210177
|View full text |Cite
|
Sign up to set email alerts
|

Prolonged fasting or clonidine can restore the defective growth hormone secretion in old dogs

Abstract: Age-related changes in GH secretion were studied in the dog. In preliminary experiments, administration of GH-relasing hormone (GHRH-40, 2 \g=m\g/kg,iv) or the \g=a\2-adrenoceptor agonist clonidine (4 \g=m\g/kg,iv) elicited significantly higher plasma GH rises in 3 to 4 years old than in 10 to 14 years old beagle dogs. The pulsatile patterns of GH secretion in both young and old dogs under baseline conditions and after prolonged fasting or clonidine administration were studied. Samples were taken every 10 min … Show more

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...
3
1
1

Citation Types

3
17
0

Year Published

1991
1991
2016
2016

Publication Types

Select...
4
2
1

Relationship

1
6

Authors

Journals

citations
Cited by 34 publications
(20 citation statements)
references
References 32 publications
(46 reference statements)
3
17
0
Order By: Relevance
“…This implied the occurrence of changes in hypotha lamic GHRH a n d /o r SS function [18,19], Interestingly, similar results were obtained by a 10-day treatment with clonidine [11]. an ct2-adrenoceptor agonist known to act via an enhanced GHRH [20,21] an d /o r a decreased SS [22] secretion.…”
Section: Discussionsupporting
confidence: 54%
See 2 more Smart Citations
“…This implied the occurrence of changes in hypotha lamic GHRH a n d /o r SS function [18,19], Interestingly, similar results were obtained by a 10-day treatment with clonidine [11]. an ct2-adrenoceptor agonist known to act via an enhanced GHRH [20,21] an d /o r a decreased SS [22] secretion.…”
Section: Discussionsupporting
confidence: 54%
“…Many factors, not mutually exclusive, can be advo cated to account for the increased GH secretion occurring dur ing fasting or CR. They include: (I) changes in the synthesis an d /o r release of hypothalamic GHRH a n d /o r SS, likely sec ondary to alterations in neurotransmitter function [11]; (2) a progressive reduction in circulating 1GF-I levels [14] with en suing decrease in the inhibitory feedback action of IGF-I on the hypothalamus an d /o r pituitary [15,16]; (3) a state of hypogly cemia triggering GH release via a direct action on hypophysiotropic neurons [ 17).…”
Section: Discussionmentioning
confidence: 99%
See 1 more Smart Citation
“…For identifying age-related differences in GH secretion, determination of the pulsatile secretion pattern of GH is much more sensitive. Indeed, the pulsatile secretion pattern of GH is significantly lower in old humans, rats, and dogs than in young individuals (Borst et al, 1994;Cella et al, 1989;Zadik et al, 1985). The higher basal plasma concentrations of ACTH and cortisol in the young dogs may indicate that the stress of handling caused a stronger activation of the pituitary-adrenocortical axis in these young dogs than in the old dogs.…”
Section: Ghrp-6mentioning
confidence: 96%
“…Both basal and stimulated GH secretion and circulating insulin-like growth factor-I (IGF-1) concentrations decline with age in several mammalian species (Corpas et al, 1992;Finkelstein et al, 1972;Muller et al, 2002;Rudman, 1985;Wilshire et al, 1995;Zadik et al, 1985). In dogs too the GH responsiveness to GH stimuli, such as GHRH and hexarelin, decreases with ageing (Cella et al, 1989(Cella et al, , 1995. Until now, the effect of ageing on the GH responsiveness to ghrelin has not been studied in the dog.…”
Section: Introductionmentioning
confidence: 99%