Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-4
pubmed:dateCreated
1999-2-2
pubmed:abstractText
During earlier study, we quantified by flow cytometry the rate of apoptotic feline lymphocytes after overnight culture. We found evidence that the sex of the animals influences the rate of apoptosis, intact females showed lower rates of apoptosis in lymphocytes cultured overnight than castrated male cats. This observation was also confirmed for cats that were previously experimentally infected with the feline immunodeficiency virus (FIV). In an attempt to find an explanation for these sexually determined differences, plasma estradiol-17beta and progesterone levels were measured by radio-immuno assay in the blood of these cats. The hormone levels were analyzed with respect to the rate of lymphocyte apoptosis. As expected, castrated males had lower blood levels of estradiol and progesterone than females. However, no overall correlation was found between hormone blood levels and rate of apoptosis under non-stimulating conditions. Interestingly, the rate of apoptosis found in lymphocytes collected from females and stimulated overnight in phytohaemaglutinin-containing medium, showed a strong negative correlation with the estradiol levels in the blood of these cats. To our knowledge, this is the first confirmation that estradiol in physiological concentrations may protect peripheral lymphocytes from apoptosis after stimulation. No correlation was found in male cats. In conclusion, these observations broaden the list of sexually determined differences of the immune system, sex and sex hormones predispose males and females for certain immune responses and dysfunctions. The present observations have to be taken into account when designing or interpreting experiments on apoptosis and, for example, evaluating the influence of a preexisting FIV infection on the rate of apoptosis. It would be highly advisable to include only spayed cats in studies on the immune system so as to minimize the influence of sex hormones.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0165-2427
pubmed:author
pubmed:issnType
Print
pubmed:day
23
pubmed:volume
65
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
151-60
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Female cats have lower rates of apoptosis in peripheral blood lymphocytes than male cats: correlation with estradiol-17beta, but not with progesterone blood levels.
pubmed:affiliation
Department of Internal Veterinary Medicine, Faculty of Veterinary Medicine, University of Zurich, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't