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R M Brenner

Publications and source records attributed to R M Brenner.

At least 55 records · Page 3Linked to original sources
PubMed1990

Sexual dimorphism characterizes baboon myocardial androgen receptors but not myocardial estrogen and progesterone receptors.

Using biochemical methods we established that estrogen receptor content and distribution and progesterone receptor content in female and male baboon myocardium did not differ between sexes. In contrast, myocardial androgen receptor distribution between cytosolic and nuclear compartments was sexually dimorphic. Female baboon myocardial androgen receptors were restricted to the cytosolic compartment, whereas male myocardial androgen receptors were distributed between the cytosolic and nuclear compartments. Using human estrogen receptor cDNA we showed that baboon aorta, myocardium and uterus contain a 6.3 kb estrogen receptor transcript. Analyses performed with human progesterone receptor cDNA established that baboon aorta and uterus contain an 8 kb progesterone receptor transcript; however, progesterone receptor transcripts were not demonstrable in baboon myocardial RNA preparations. Because relative hybridization signal intensity reflected known uterine and aortic progesterone receptor content, failure to detect progesterone receptor transcripts in myocardial preparations may reflect sensitivity limitations and the fact that aortic progesterone receptor content is 5-fold greater than that of myocardium. Immunocytochemical analyses demonstrated that baboon myocardial progesterone receptors were present in greater than 25% of myocytes and generally absent from other myocardial cells. Our studies establish that: (1) gonadal steroid hormone receptor gene transcription occurs in cells of the baboon cardiovasculature, (2) these steroid hormone receptors may be physiologically functional, and (3) gonadal steroid hormone receptors may be restricted to specialized cells of the cardiovasculature.

Animals↗
PubMed1990

Estrogen and progestin receptors in the reproductive tract of male and female primates.

With the aid of monoclonal antibodies specific to the estrogen and progestin receptors, we have examined the cellular localization of these proteins in the reproductive tract of male and female macaques. Two striking findings have resulted from our work with these new reagents. First, these receptors are detectable only in cell nuclei, regardless of hormonal treatment, and second, they are often detectable in stromal, but not epithelial cells when the epithelial cells undergo various estrogen or progestin-dependent events. The latter observation has led us to conclude that stromal cell-epithelial cell interactions may play previously unappreciated roles in the hormonal control of the primate reproductive tract. The lines of evidence that have drawn us to this conclusion will be reviewed.

Animals↗
PubMed1990

Estrogen receptor in the ductuli efferentes, epididymis, and testis of rhesus and cynomolgus macaques.

We obtained the testes, ductuli efferentes, and epididymides from adult rhesus and cynomolgus macaques and examined these tissues for estrogen receptors (ER) with immunocytochemistry (ICC) and a sucrose gradient assay. Both techniques employed monoclonal antibodies prepared against ER, and both showed that high concentrations of ER were present OFFy in the ductuli efferentes. Moreover, all specific staining was confined to the nuclei of the nonciliated, absorptive epithelial cells. The quantity of salt-extractable ER in the ductuli efferentes (834 +/- 161 [SEM] fmol/mg DNA [n = 8]) did not differ significantly from the amounts measured with the identical assay in oviducts and endometrium of estrogenized female macaques. Testes and epididymides of macaques had no specific staining by ICC and barely detectable amounts by biochemical analysis (7 +/- 4 [n = 3], 8 +/- 2 [n = 5], 33 +/- 16 [n = 3], and 6 +/- 3 [n = 8] fmol/mg DNA for testis and caput, corpus, and cauda epididymis, respectively). The functional significance of the high levels of ER in the ductuli efferentes of macaques remains to be determined.

Animals↗
PubMed1990

Modulation of osmolytes in MDCK cells by solutes, inhibitors, and vasopressin.

MDCK cells accumulate organic osmolytes in response to hyperosmotic NaCl-supplemented medium. We examined time course and inhibitor sensitivity of myo-inositol, sorbitol, and glycerophosphorylcholine (GPC) accumulation in MDCK cells exposed to hyperosmotic NaCl-, D-glucose-, or mannitol-supplemented media. In NaCl medium, cells preferentially accumulated inositol and GPC. In comparison, in glucose medium cells preferentially accumulated sorbitol and GPC. Inositol demonstrated a late (72-96 h) accumulation in glucose medium, although less than in NaCl medium. Mannitol medium did not significantly stimulate accumulation of any of these three osmolytes at 24 h, suggesting that hyperosmolality alone is not sufficient stimulus for their accumulation in this time frame. GPC accumulation was very rapid in glucose medium, and fell to the level induced by NaCl medium at 96 h (approximately 50 nmol/mg protein). Inositol and sorbitol accumulated more gradually, each reaching greater than 400 nmol/mg protein after 96 h. Sorbitol was still accumulating at 96 h, whereas inositol plateaued at 72-96 h. Phlorizin or sorbinil blocked accumulation of inositol or sorbitol, respectively. Sorbitol and GPC accumulation in glucose medium were partially inhibited in absence of serum or in presence of 1 microM vasopressin. Thus NaCl and glucose appear to stimulate specific cellular mechanisms responsible for accumulation of inositol, sorbitol, and GPC in MDCK cells. This accumulation is also modulated by constituents of serum.

Animals↗
PubMed1990

Regulation and localization of estrogen and progestin receptors in the pituitary of steroid-treated monkeys.

PRL increases during pregnancy in primates with rising levels of placental estradiol (E) and progesterone (P). However, while E will increase PRL secretion in monkey pituitary cell cultures, P has no effect. We recently localized progestin receptors (PR) to gonadotropes, but not lactotropes, with an immunocytochemical technique to double stain monkey pituitary cell cultures. The following studies were performed to confirm the immunocytochemical localization of PR in intact pituitary tissue and to determine the effect of E and P on the levels of estrogen receptors (ER) and PR in the pituitary. ER and PR levels were determined in the endometrium of the same animals for an internal comparison. Thirteen adult cycling female cynomolgus monkeys were ovariectomized and treated for 28 days with 1) an empty Silastic capsule (Spay), 2) a 2-cm E-filled capsule (E), or 3) a 2-cm E-filled capsule for 14 days plus a 6-cm P-filled capsule implanted for an additional 14 days (E + P). Blood samples were drawn daily for assay of serum E, P, and PRL levels. Serum PRL was not significantly affected by E, but the sequential addition of P significantly increased serum PRL levels over those observed in Spray animals. The anterior pituitary and endometrium were removed for measurement of ER and PR levels by a sucrose gradient shift assay incorporating monoclonal antibodies against ER and PR. Pituitary ER levels did not vary significantly with steroid treatment (158.2 +/- 33.6, 135.5 +/- 24.9, 104.3 +/- 13.4 fmol/mg DNA in Spay, E, and E + P animals, respectively). Pituitary PR levels were undetectable in Spay animals, were induced by E (393.3 +/- 53.4 fmol/mg DNA), and were suppressed to undetectable levels by the addition of P. A portion of the pituitary was frozen for immunocytochemical single staining for ER, PR, PRL, and LH and double staining for PRL + PR and LH + PR. ER staining was observed in many parenchymal cells, but there was no apparent change with steroid treatment. PR staining was absent in the Spay animals; many PR-positive cells were observed in E-treated females, and only a small number of faintly staining cells were detected in the E + P animals. Double staining for PRL + PR and LH + PR revealed PR in gonadotropes, but not lactotropes. In conclusion, PR, but not ER, are regulated by E and P in the monkey pituitary. Importantly, PR is regulated within gonadotropes, but not lactotropes. Therefore, P probably increases PRL secretion through a hypothalamic action.

Animals↗
PubMed1990

Uterine estrogen receptors are increased by RU486 in late pregnant rhesus macaques but not after spontaneous labor.

Progesterone withdrawal as a mechanism for parturition in primates is controversial. The progesterone antagonist RU486, given in late pregnancy to rhesus monkeys at a dose of 47 mmol/kg.day (20 mg/kg.day), causes an increase in uterine activity, but not the expected increase in amniotic fluid prostaglandins or cervical dilatation. We, therefore, studied the effect of RU486 on estrogen receptor (ER) localization and concentration in reproductive tract tissues in rhesus monkeys during late gestation and after spontaneous labor at term. Distribution of ER in pregnant uterine tissues was studied by immunocytochemical techniques and quantified by a biochemical assay, both of which employed a monoclonal antibody specific for ER. ER was not present in amnion and chorion by immunocytochemical investigation; however, a significant increase in receptor staining was seen in decidua and myometrium after RU486 treatment compared to that in both pregnant control tissues and parturient tissues. Sucrose gradient assay of nuclear (n) and cytosolic (c) ER revealed a low level of ER (expressed as fmol of estradiol bound/mg of DNA) in pregnant and parturient decidua (pregnant: nER = 7.3 +/- 2.4, cER = 17.1 +/- 6.4; parturient, nER = 7.7 +/- 3.1, cER = 16.4 +/- 8.8) and myometrium (pregnant: nER = 21.7 +/- 4.1, cER = 20.8 +/- 5.3; parturient: nER = 30.0 +/- 2.8, cER = 10.7 +/- 6.7). In contrast, tissues collected from RU486-treated animals contained high levels of ER in decidua (nER = 52.3 +/- 16.8, cER = 240.5 +/- 145.3) and myometrium (nER = 77.0 +/- 19.2; cER = 66.5 +/- 31.6). We conclude that 1) the increase in ER in decidua and myometrium after RU486 treatment is the result of a decrease in the inhibitory action of progesterone on ER and documents the progesterone receptor antagonism by RU486 during induced myometrial contractility in late pregnant rhesus monkeys; 2) the absence of ER from amnion and chorion indicates that the normally observed increase in prostaglandin production by rhesus fetal membranes during labor is not mediated by ER; and 3) the absence of a change in the concentration of ER in decidua and myometrium from pregnant control monkeys and those in spontaneous labor indicates that an increase in ER (and, by inference, a withdrawal of receptor-mediated progesterone inhibition) is not part of the normal events in preparation for parturition in primates.

Amnion↗
PubMed1990

Are human luteinizing granulosa cells a site of action for progesterone and relaxin?

Specific nuclear staining for progesterone receptor (PR) was detected by immunocytochemistry in human granulosa cells (GCs) obtained from in vitro fertilization protocols. The percent of PR-positive cells (60% to 80%) remained unchanged during 7 days of culture in media containing fetal calf serum, in the absence or presence of human chorionic gonadotropin (hCG) or the progesterone antagonist RU486. Progesterone (P) production by GCs cultured on extracellular matrix from bovine corneal endothelial cells was stimulated by hCG and prostaglandin E2 (PGE2). However, addition of RU486 or human relaxin had no effect on control, hCG-, or PGE2-stimulated P production. Thus, the receptor data are consistent with an autocrine action of P in luteinizing GCs, but initial experiments in cell culture did not define a role for P or relaxin in modulating luteal steroidogenesis.

Cells, Cultured↗
PubMed1989

Early effects of uranyl nitrate on respiration and K+ transport in rabbit proximal tubule.

The mechanisms by which uranyl nitrate (UN) is toxic to the proximal tubule are incompletely understood. To define these further we studied potassium (K+) transport and oxygen consumption (QO2) in rabbit proximal tubule suspensions in vitro immediately after exposure to UN using extracellular O2- and K+-sensitive electrodes. UN caused a cumulative dose-dependent inhibition of proximal tubule QO2, with a threshold concentration of 5 x 10(-5) M. Kinetic analysis suggested two patterns of cell injury: a higher affinity inhibition of QO2 with a Ki of 5 x 10(-4) M, and a lower affinity inhibition of QO2 with a Ki of 10 mM. QO2 was studied in detail in the presence of these Ki concentrations of UN to define the initial cellular events. The results indicated that different cellular processes displayed different sensitivities to UN. At submillimolar concentrations UN caused progressive selective inhibition of ouabain-insensitive QO2 (15% inhibition at 2 minutes). Ouabain-sensitive QO2 and nystatin-stimulated QO2 were not affected, suggesting that Na+,K+-ATPase activity and its coupling to mitochondrial ATP synthesis were intact. Direct measurement of proximal tubule net K+ flux confirmed that Na+,K+-ATPase activity was unchanged. Similarly, UN did not inhibit basal (state 4) or ADP-stimulated (state 3) mitochondrial QO2 in digitonin-permeabilized tubules, confirming that the mitochondria were intact. In contrast, higher concentrations of UN (greater than or equal to 1 mM) caused rapid inhibition of QO2 and net K+ efflux, due to inhibition of Na+,K+-ATPase activity and mitochondrial injury.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Diphosphate↗
PubMed1989

Estrogen and progestin receptor immunocytochemistry in lactotropes versus gonadotropes of monkey pituitary cell cultures.

The distribution of estrogen receptors (ER), progesterone receptors (PR), PRL, and gonadotropins in different cell types of the monkey pituitary was examined by immunocytochemical (ICC) labeling of pituitary cell cultures. Dispersed monkey pituitary cells were cultured on extracellular matrix and in serum-free medium for 6-14 days. Individual cultures were singly stained for ER, PR, PRL, LH, and FSH or double labeled for PR and one of the protein hormones. ICC reaction product localizes over the nuclei of cells that are positive for the steroid receptors, whereas reaction product localizes over the cytoplasm of cells that are positive for the protein hormones. Sixty-one percent of the parenchymal cells were positive for PRL, while 1-3% were positive for LH or FSH. Sixty-two percent of the parenchymal cells were ER positive. ER staining was localized over the nuclei of two morphologically distinct cell types. One cell type is smaller and more prevalent than the second cell type. Based on single staining for each of the protein hormones, we propose that the smaller cells are lactotropes, and the larger cells are gonadotropes. PR-positive cells averaged 7.7% of the parenchymal cells. Double ICC staining for PR and the protein hormones demonstrated that PR localize in the nuclei of gonadotropes, but not lactotropes, of monkey pituitary cell cultures. The absence of PR in lactotropes is consistent with our observation that progesterone has no direct effect on PRL secretion in monkey pituitary cell cultures. In contrast, the presence of PR in gonadotropes suggests that progesterone may act directly at the pituitary to modulate gonadotropin secretion in the primate. In conclusion, ER are present in both lactotropes and gonadotropes. PR are present in gonadotropes, but not lactotropes, of the primate pituitary.

Animals↗
PubMed1989

Proenkephalin gene expression in the primate uterus: regulation by estradiol in the endometrium.

Proenkephalin mRNA has previously been shown to be expressed in the rodent uterus with varying levels during the estrous cycle. To examine for the potential regulation of proenkephalin gene expression by steroid hormones in a primate displaying a menstrual cycle and to define the functional tissue within the uterus expressing this transcript, we have used Northern blot analysis of extracted RNA from isolated uterine tissue subtypes from normal adult rhesus macaques obtained during the menstrual cycle and from ovariectomized females under different physiological steroid hormone treatments. A strong band of proenkephalin mRNA of 1.3 kilobases was detected almost exclusively in the proliferative endometrium from monkeys in the follicular phase of the cycle. No proenkephalin mRNA was detected in secretory endometrium obtained from monkeys in the luteal phase. When ovariectomized macaques were implanted with silastic capsules of 17 beta-estradiol, proenkephalin mRNA was detected in the endometrium but not the myometrium of the estradiol-treated animals. No proenkephalin mRNA was detected in ovariectomized control animals. Under these conditions, we were unable to detect proenkephalin mRNA in ovariectomized macaques implanted with separate silastic capsules of 17 beta-estradiol and progesterone or in decidual tissue from early or late pregnancy. These results suggest that in the primate uterus 1) proenkephalin mRNA is expressed primarily in the endometrium of the uterus, 2) expression of the proenkephalin gene is regulated by 17 beta-estradiol in the endometrium, and 3) this effect of estradiol is antagonized by progesterone.

Animals↗
PubMed1989

Chlamydia trachomatis oculogenital infection in the subcutaneous autotransplant model of conjunctiva, salpinx and endometrium.

The subcutaneous pocket model of salpingeal, endometrial, and conjunctival autografts for studying Chlamydia trachomatis infection in monkeys is described. Portions of the salpinx that were transplanted included fimbria, ampulla, and isthmus. The model is an extension of the original model which consists of either salpingeal fimbria or conjunctive autografts. Transplantation of the ampulla portion of the Fallopian tube enabled us to increase the number of pockets or test sites. Salpingeal and conjunctival autografts could be established during a single surgery. In addition, it is possible to autotransplant endometrium and provoke endometritis. The autografts were shown to be susceptible to C. trachomatis infection. Preliminary rechallenge experiments showed infection of the subcutaneous transplants may induce immunity, indicating the model may be used for immunity and vaccine studies. Simultaneous transplantation of different parts of the oviduct, endometrium, and conjunctive should expand the usefulness of the subcutaneous model in other studies on mixed infections or immune responses to infection.

Animals↗
PubMed1988

Accumulation of major organic osmolytes in rat renal inner medulla in dehydration.

Osmotically active organic solutes, osmolytes, exist at high concentrations in the renal inner medulla; however, their modulation during antidiuresis remains largely undefined. Renal osmolyte levels were measured by nuclear magnetic resonance spectroscopy and biochemical assays in perchloric acid extracts from normal and dehydrated (3 days) rats. Dehydration increased urine osmolality from 1,503 to 3,748 mosmol/kg and inner medullary urea content from 2,036 to 4,405 nmol/mg protein. In addition, inner medullary trimethylamines [glycerophosphorylcholine (GPC) and betaine] and polyhydric alcohols (inositol and sorbitol) significantly increased by 95 and 78%, respectively. Ninhydrin-positive substances (amino acids), although abundant, were unchanged. Renal cortex also contained GPC, betaine, and inositol but only inositol increased with dehydration. Analysis of correlations among inner medullary osmolytes showed that only GPC was consistently elevated by dehydration and was not directly correlated with the other osmolytes. In contrast, betaine and inositol contents were linearly related to each other and both tended to rise only when sorbitol content was unchanged. In conclusion, the major osmolytes in the rat renal inner medulla can increase during antidiuresis but they are regulated in a complex manner.

Animals↗
PubMed1988

The effect of simultaneous versus sequential estradiol and progesterone treatments on prolactin production in monkey pituitary cell cultures.

Dispersed monkey pituitary cells were cultured in serum-free medium and on extracellular matrix for 30 days. After 10-14 days with only insulin, transferrin, and selenium (ITS), the addition of estradiol (E) significantly increased PRL secretion compared to that in vehicle-treated controls. Simultaneous addition of E plus progesterone (P) increased PRL secretion similarly to E alone. PRL secretion in cultures treated with E plus P after 10 days induction by E was also similar to that in cultures maintained continuously in E. PRL secretion declined in wells switched from E to P and in wells switched from E back to vehicle, relative to that in wells maintained continuously in E. Estrogen receptors (ER) were detected in whole pituitary tissue and in serum-free pituitary cultures with a monoclonal antiestrogen receptor antibody (H222) in a sucrose density gradient shift assay. Immunocytochemical staining for ER with the same antibody also showed positive cell nuclei in serum-free pituitary cultures. In summary, ER are maintained in monkey pituitary cells during tissue culture, and PRL production can be further increased by E treatment after long term serum-free culture. Neither simultaneous nor sequential E plus P treatment alters PRL secretion compared to E alone.

Animals↗
PubMed1988

Estrogen and progestin receptors and aromatase activity in rhesus monkey prostate.

We examined nuclear estrogen receptors (ER) and progestin receptors (PR) in the rhesus monkey prostate. Tissues were obtained from six intact males, five untreated castrates, six castrates treated with testosterone (T) for 6 weeks, and four castrates treated with estradiol (E2) for 6 weeks. Samples of the caudal lobe were either assayed biochemically for ER or stained immunocytochemically (ICC) with monoclonal antibodies against the ER or PR. Prostates from untreated castrates had significantly more ER than tissues from intact or T-treated castrates. In E2-treated castrates, ER number increased compared to that in intact and T-treated castrates. With ICC, ER was found only in the nuclei of the fibroblasts and smooth muscle cells of the stroma, not the glandular, ductal, or urethral epithelial cells. Intact and T-treated castrates had a very small number of positive cells, while untreated and E2-treated castrates had a significantly increased number of positive ER cells in the fibromuscular stroma. With ICC, PR was absent in intact or T-treated animals and barely evident in untreated castrates, but was significantly increased in the fibromuscular stroma of E2-treated castrates. The histological preparations indicated there was no stromal hypertrophy in the E2-treated castrates, but the E2 treatment did cause dilation of the glandular acini. Aromatase activity was measured in prostatic microsomes with a radiometric assay. Levels were low (3-30 fmol/h.mg protein) compared to those in brain and placenta, and no differences in activity were seen between castrates and T-treated castrates. Our data demonstrate that androgens can suppress the level of nuclear ER in the rhesus prostate, and that E2 treatment of castrates can induce PR in the same cells as those that contain ER. Thus, under appropriate conditions, estrogens could affect the rhesus prostate through a receptor-mediated pathway.

Animals↗
PubMed1988

Immunocytochemical localization of estradiol and progesterone receptors in the monkey ovary throughout the menstrual cycle.

Both estradiol and progesterone may act locally to modulate ovarian function in various species. This study examined the distribution of estradiol and progesterone receptors (ER and PR, respectively) within the primate ovary throughout the menstrual cycle. Ovaries were collected from rhesus or cynomolgus monkeys during the early, mid-, and late (n = 3-6/stage) follicular and luteal phases of the cycle. The tissues were processed for indirect immunocytochemical localization of receptors with specific monoclonal antibodies against ER (H222 and D75) and PR (JZB39). Specific immunocytochemical staining, as determined by comparing adjacent tissue sections incubated with either receptor antibodies or a nonspecific antibody, was exclusively nuclear. Both ER and PR were localized in the germinal epithelium of ovaries at all stages of the cycle. ER was not detected in any other ovarian structure (i.e. stroma, follicles, interstitial tissue, or corpora lutea) regardless of the stage of development. However, ER was detected in other estrogen-responsive tissues, e.g. the oviduct of the monkey and corpora lutea of the pseudopregnant rabbit. In the monkey ovary, PR was detected in stromal and interstitial tissues as well as theca interna and externa of healthy and atretic follicles at all stages of the cycle. The granulosa cells of some primordial and primary follicles demonstrated staining for PR. However, the granulosa layer of follicles that developed beyond the primary stage were consistently negative for PR. Only the granulosa layer of large preovulatory follicles that showed signs of luteinization after the LH surge showed staining for PR equivalent to that in the theca. Monkey corpora lutea exhibited specific nuclear staining for PR. Moreover, the percentage of receptor-positive nuclei in the corpus luteum varied (P less than 0.05) between the early (28 +/- 3%), mid (48 +/- 1%)-, and late (4 +/- 2%) luteal phase of the cycle. Nonfunctional (serum progesterone less than 0.5 ng/ml) regressing corpora lutea did not exhibit for staining for PR. Luteal cells that were PR positive also contained histochemically detectable 3 beta-hydroxysteroid dehydrogenase. These data are consistent with the concept of a receptor-mediated autocrine or paracrine role for progestins, but not estrogens in the gametogenic and endocrine functions of the primate ovary throughout the menstrual cycle.

3-Hydroxysteroid Dehydrogenases↗
PubMed1988

Immunocytochemistry of the estrogen receptor in spontaneous endometriosis in rhesus macaques.

Immunocytochemical, biochemical, and histologic analysis of endometriotic lesions and endometria from rhesus macaques with endometriosis revealed several distinctions between ectopic and eutopic endometrium. In lesions, unlike endometrium, neither the mean percentages of estrogen receptor positive (ER+) cells nor the total ER content changed significantly during the menstrual cycle. In eutopic endometria, ER staining in both stromal and epithelial cells increased and decreased synchronously during the cycle, but in endometriotic lesions, such synchrony was lacking. Moreover, in lesions, unlike endometria, the percentage of ER+ cells was low in the stroma and highly variable in epithelium throughout the cycle. These data, taken together, indicate a defect in the hormonal regulation of ER in endometriotic lesions of monkeys.

Animals↗
PubMed1988

Wound healing in the sex skin of pig-tailed macaques.

We studied wound healing in methacrylate- and araldite-embedded sex skin, a unique tissue that embodies the properties of friction surface and hairy skin. The largely light-microscopic observations were supplemented with transmission electron microscopy. The time of epidermal bridging was directly dependent on how closely apposed were the wound margins. Repair in the dermis always occurred more rapidly in the upper and in the lower parts of the wound gap than in the middle. Early in healing, the original epidermis cut off a wedge of skin in the upper wound margin (precocious remodeling) and cast it off at the margin of the clot. Remodeling (collagen resorption) inside the wound gap is accomplished primarily by fibroclasts. All mast cells in the vicinity of the wound attain fatty vacuoles. Adipose tissue near the wound undergoes lipolysis: the adipocytes gradually become smaller and their cytoplasm reticulated as small fat vesicles are extruded in the interstitium; fibroblasts, macrophages, polymorphonuclear leukocytes (PMNs) and mast cells readily phagocytose the fat vesicles. Elastic fibers do not participate in wound healing. There was no evidence of elastic fiber formation in granulation tissue.

Animals↗