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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3 Pt 2
|
| pubmed:dateCreated |
1982-6-24
|
| pubmed:abstractText |
The New England Deaconess Hospital (NEDH) rat provides a valuable model with which to study pheochromocytoma (P); 59% of male rats 700 to 900 days old and 81% of those 900 days or older developed spontaneous P. One transplantable P (P259), when implanted into other NEDH rats, markedly increased plasma norepinephrine and dopamine as well as blood pressure, and usually caused death within 4 weeks. Even without P, about 83% of NEDH rats became hypertensive by 131/2 weeks of age and remained moderately hypertensive until 2 years of age when some animals developed spontaneous P and hypertension became severe. Whether a common mechanism is responsible for early appearance of hypertension and later development of P remains to be determined. Hypophysectomized NEDH rats remained normotensive or slightly hypotensive despite marked elevations of plasma norepinephrine and dopamine caused by P259 implantation; furthermore, survival was prolonged to 3 months. Catecholamine concentrations in plasma and RBC were usually quite similar, indicating that red blood cells play a significant role in inactivating circulating catecholamines. Unlike the normal adrenal, P259 in NEDH rats contains mainly norepinephrine and dopamine with little epinephrine; it appears that P259 is deficient in the enzyme phenylethanolamine-N-methyltransferase (PNMT), which converts norepinephrine to epinephrine. Why hypophysectomy prevents hypertension and prolongs life in rats with P259 implants is unclear; adrenal cortical and thyroid deficiency may play a role. Preliminary observations indicate that hypophysectomy can prevent spontaneous development of P in NEDH rats.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:issn |
0194-911X
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
4
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
200-7
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:7068205-Adrenal Gland Neoplasms,
pubmed-meshheading:7068205-Aging,
pubmed-meshheading:7068205-Animals,
pubmed-meshheading:7068205-Blood Pressure,
pubmed-meshheading:7068205-Catecholamines,
pubmed-meshheading:7068205-Dopamine,
pubmed-meshheading:7068205-Epinephrine,
pubmed-meshheading:7068205-Erythrocytes,
pubmed-meshheading:7068205-Hypertension,
pubmed-meshheading:7068205-Hypophysectomy,
pubmed-meshheading:7068205-Male,
pubmed-meshheading:7068205-Neoplasm Transplantation,
pubmed-meshheading:7068205-Neoplasms, Experimental,
pubmed-meshheading:7068205-Norepinephrine,
pubmed-meshheading:7068205-Pheochromocytoma,
pubmed-meshheading:7068205-Rats,
pubmed-meshheading:7068205-Rats, Inbred Strains,
pubmed-meshheading:7068205-Vanilmandelic Acid,
pubmed-meshheading:7068205-Water-Electrolyte Balance
|
| pubmed:articleTitle |
Effect of pheochromocytoma and hypophysectomy on blood pressure and catecholamines in NEDH rats.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|