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T T Turner

Publications and source records attributed to T T Turner.

At least 37 records · Page 2Linked to original sources
PubMed1995

Protein synthesis and secretion by the rat caput epididymidis in vivo: influence of the luminal microenvironment.

The role of intraluminal factors in regulating the functions of the epididymal epithelium is unknown and virtually unexplored. Simultaneous in vivo microperfusion and microperfusion procedures were carried out on rat caput epididymal tubules to examine the effects of the intraluminal microenvironment on protein synthesis and secretion. Caput tubules were perifused with 35S-methionine for 3 h while the tubule lumen was subjected to a stop-flow perfusion of either native caput content from another epididymis (NCC), artificial caput fluid containing no testicular factors (ACF), or rete testis fluid (RTF). Protein synthesis and secretion were measured quantitatively as trichloroacetic acid- (TCA) precipitable 35S-methionine-labeled proteins (cpm/microliter) and qualitatively as autoradiograms of electrophoresed 35S-methionine-labeled proteins. Electrophoresed proteins, i.e., those in fluids collected by micropuncture, were: perifused interstitial fluid (IF), lumen fluid from the perifused but not perfused length of tubule (LF), and the perfusion fluid (PF) re-collected from the tubule lumen. Undiluted tubule extract (TE) of the perfused length of tubule was also analyzed. ACF in the lumen caused a significant reduction in proteins synthesized and secreted by the epithelium, and RTF in the lumen returned protein synthesis and secretion to control values. For example, TCA-precipitable 35S-methionine-labeled proteins in TE of tubules perfused with NCC, ACF, or RTF were 107.6 +/- 13.1, 58.9 +/- 6.9, and 121.9 +/- 19.7 x 10(3) cpm/microliters, respectively. Autoradiograms reinforced this data. Subsequently, tubules were perfused with ACF or ACF containing physiological concentrations of sex hormone-binding globulin (SHBG; an androgen-binding protein [ABP] homolog), 5 alpha-dihydrotestosterone (DHT), or SHBG+DHT.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

The venous anatomy of experimental left varicocele: comparison with naturally occurring left varicocele in the human.

OBJECTIVE: To determine the effect of experimental left varicocele on the anatomy of the veins serving the rat testis and to compare that anatomy to known patterns of vascular drainage from the human testis with and without varicocele. DESIGN: Vascular maps were made of the effluent vessels from the rat testis in control animals and those with a 30-day experimental left varicocele. Consensus maps were arrived at and these were compared to published reports of the pertinent venous anatomy in humans with and without varicocele. SETTING: Research laboratory. RESULTS: The major route of blood leaving the rat testis was confirmed to be the spermatic vein, but nine common collaterals were also found to exist. Four of these collaterals became more pronounced with experimental varicocele as did several dilated perineal veins. These latter vessels all led to the iliac vein. The vasculature of the rat experimental varicocele model shares some important anatomical features with human varicocele anatomy. CONCLUSIONS: Varicocele in humans and in the rat model causes a redistribution of blood flow from a route primarily out the spermatic vein to routes leading to the iliac vein. The redistribution is similar but not identical.

Animals↗
PubMed1994

Assessment of protein synthesis and secretion by rat seminiferous and epididymal tubules in vivo.

In vivo microperifusion and micropuncture were used to study tubule protein synthesis and proluminal secretion by the male reproductive tract in vivo. Seminiferous and caput and cauda epididymal tubules were perifused for 3 h. with [35S]-methionine. Perifused interstitial fluid (IF), lumen fluid (LF), and tubule extract (TE) were collected. Proteins were separated by SDS-PAGE, and autoradiograms were developed. Trichloroacetic acid precipitable proteins in each fluid were determined and a protein synthesis index (PSI) was calculated. PSI values demonstrated that the cauda epididymis synthesized less protein in vivo than did either seminiferous or caput tubules. Seminiferous tubules synthesized and secreted into the tubule lumen a relatively constant panel of proteins. Epididymal tubules synthesized and secreted proteins in a region-specific manner. In the caput epididymis the most prominent secreted bands were consistent with the heavy and light chains of epididymal clusterin. In the cauda epididymis, the most prominent synthesized and secreted protein was a 25 kDa protein consistent with the protein D. The above approach to studying protein synthesis and secretion will allow direct study of the physiological and pathophysiological effects on this important epithelial function in vivo.

Animals↗
PubMed1994

Interleukin-1 beta stimulates interleukin-6 production in placental villous core mesenchymal cells.

Interleukin-6 (IL-6) is a pleiotropic mediator of immune function and a growth factor for a variety of hematopoietic cell types. Because IL-1 beta is known to induce IL-6 production in nonplacental mesenchymal cells and is locally produced by maternal decidua, this study was designed to determine whether IL-1 beta could regulate IL-6 production by second trimester placental villous core mesenchymal cells (VCMC) in vitro. VCMC were prepared for culture by enzymatic digestion of placentas (14-20 weeks gestation; n = 7). Immunohistochemistry performed on the confluent cells demonstrated that more than 95% of the cells had a fibroblast-like morphology and were vimentin positive, less than 5% were leukocyte common antigen (CA-45) positive, and no trophoblast contamination was demonstrated by the lack of cytokeratin staining. In dose-response experiments, a specific dose-response induction of IL-6 mRNA expression and IL-6-immunoreactive protein production by IL-1 beta was demonstrated; this was first seen at 100 pg/ml IL-1 beta [455 +/- 191 ng/ml (+/- SEM); controls, 42 +/- 16 ng/ml; P < 0.05]. In time-course studies, the addition of 10 ng/ml IL-1 beta significantly increased IL-6 production rates; this was first seen at 8 h of culture and increased in a linear fashion up to 48 h. At 48 h of culture, IL-6 levels were 17 times higher in treated VCMC (861 +/- 179 ng/ml) compared to those in nontreated VCMC (51 +/- 14 ng/ml). In summary, IL-1 beta stimulates VCMC IL-6 production in a specific dose- and time-dependent manner. From these results, we conclude that VCMC are an important source of IL-6 in second trimester placenta and that production of placental IL-6 be may regulated by decidual IL-1 beta.

Cells, Cultured↗
PubMed1993

Restoration of spermatogenesis and subsequent fertility by direct intratesticular hormonal therapy.

Testosterone-laden microspheres (TLM) were used in an attempt to restore spermatogenesis and sustain fertility in rats with previously suppressed gonadal function. Adult rats received 62.5 micrograms. gonadotropin-releasing hormone antagonist (GnRH-antagonist) per day for 15 days prior to being divided into three groups: 1) animals to be examined immediately, 2) animals to continue receiving 62.5 micrograms. GnRH-antagonist per day alone, and 3) animals to continue receiving GnRH-antagonist + a single intratesticular injection of 20 mg. TLM per testis. Unoperated control and sham-operated animals were also studied. Testicular interstitial fluid (TIF) testosterone concentrations, testicular sperm production and fertility were assessed 105 days after initiation of the experiment. Testicular interstitial fluid testosterone concentrations and sperm production were significantly reduced from control values after the initial 15-day GnRH-antagonist treatment (p < .05). After 105 days of GnRH-antagonist treatment, these values were further reduced (p < .05), but the TIF testosterone and sperm production values of GnRH-antagonist treated animals receiving TLM supplementation were not different from those of controls (p < .05). Fertility trials were also performed. Animals which had received GnRH-antagonist alone for 90 days were completely infertile, but animals receiving GnRH-antagonist + TLM for 90 days had fertility values not different from those of control animals (p < .05). Thus, spermatogenesis reduced because of testicular insufficiency was restored to normal, as was fertility, by intratesticular administration of TLM. This technique has possible clinical applications in selected groups of infertile men.

Animals↗
PubMed1993

Spermatic cord torsion: loss of spermatogenesis despite return of blood flow.

Previous work in animal models has recapitulated and refined the clinical observation that longer periods of testicular torsion are associated within increased damage to the testis. Minimum times of damage-inducing torsion have not been established, however, nor has it been established to what degree blood flow returns to the testis on examination several hours or days after the torsion repair. Adult male rats were subjected to 0.5-h or 1.0-h 720 degrees torsion and examined for effects on testis weight, histology, and daily sperm production (DSP). None of the parameters examined were affected by 0.5-h, but all were affected by 1.0-h torsion. In a subsequent experiment, adult rats were subjected to unilateral, 1-h, 720 degrees torsion, and bilateral testicular blood flow as measured by radiolabeled microsphere distribution was determined during torsion and 4 h, 24 h, 2 days, 7 days, 15 days, and 30 days after repair of torsion. Ipsilateral testicular blood flow was reduced 94% during torsion. Blood flow was not significantly different from control or contralateral values by 4 or 24 h after repair of torsion. In spite of this return of blood flow, testis weights were significantly reduced by half by 7 days after torsion repair and spermatogenesis was clearly disrupted upon histological examination 30 days after torsion repair. Increasing the time of torsion to 2 or 4 h did not inhibit return of blood flow to the testis as measured 48 h after torsion repair. Unless the testis is infarcted, testicular blood flow in the rat model returns to normal after torsion repair.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Interleukin-1 is induced in the human placenta by endotoxin and isolation procedures for trophoblasts.

Although freshly obtained placenta contains little or no interleukin-1 (IL-1) mRNA, placenta and isolated trophoblast have been reported to produce significant quantities of bioactive IL-1 in vitro. The present study was designed to determine if endotoxin, a common contaminant of culture medium, and trophoblast isolation procedures could induce IL-1 expression in the placenta. Tissue-extractable IL-1 alpha and IL-1 beta immunoreactive proteins were readily detected in fresh placental membranes, but not placental villi. As little as 10 ng/mL endotoxin were found to induce the expression of IL-1 alpha and IL-1 beta mRNA in intact placental villi cultured in vitro. Intact placenta cultured in the presence of 1.0 microgram/mL endotoxin demonstrated expression of IL-1 alpha and IL-1 beta mRNA and cumulative production and release of immunoreactive IL-1 alpha and IL-1 beta into the medium during 24 h of culture. Placenta incubated in endotoxin-free medium, however, exhibited no detectable IL-1 alpha or IL-1 beta mRNA expression and little or no release of IL-1 alpha or IL-1 beta immunoreactive protein into the medium. When trophoblast cells were freshly isolated by enzymatic digestion, followed by Percoll separation at reduced temperatures to inhibit cell activation, no IL-1 alpha or IL-1 beta mRNA expression was initially detectable. However, IL-1 alpha and IL-1 beta mRNA in isolated trophoblast cells were induced after 30 min of culture in endotoxin-free medium, with maximal induction at 4 h. These results suggest that normally the placenta produces very little, if any, IL-1, and that endotoxin and trophoblast isolation procedures induce IL-1 expression in placental tissues cultured in vitro.

Cell Separation↗
PubMed1991

Different mechanisms are responsible for 3H-androgen movement across the rat seminiferous and epididymal epithelia in vivo.

Mechanisms involved in the maintenance of the microenvironment of the seminiferous and epididymal tubules were examined in a series of experiments utilizing in vivo microperifusion, microperfusion, and micropuncture. Intraluminal 3H-androgen concentrations in seminiferous tubules increased linearly as interstitial 3H-androgen concentrations increased from 10 nM to 2,000 nM, but in caput epididymidal tubules, intraluminal 3H-androgen concentrations increased hyperbolically across the same range of peritubular 3H-androgen concentrations. Intraluminal 3H-androgen concentrations in the caput epididymidis did not rise above approximately 340 nM even if peritibular 3H-androgen concentrations exceeded 2,000 nM. Perifusion of caput tubules with 0.1 mM dinitrophenol or potassium cyanide or 100 micrograms/ml cyclohexamide significantly reduced proluminal 3H-androgen movement, but tubules perifused with control medium would not support antigrade 3H-androgen movement in the absence of native lumen fluids which contain androgen-binding protein. Antigrade proluminal 3H-androgen movement was not inhibited by competition with estradiol at ten-times 3H-androgen concentrations. Thus, energy-requiring protein synthesis is necessary for antigrade 3H-androgen movement in the caput epididymidis, but the mechanism for the interaction of intracellular protein(s) and 3H-androgen movement remains undetermined.

2,4-Dinitrophenol↗
PubMed1990

On the maintenance of male fertility in the absence of native testosterone secretion: site-directed hormonal therapy in the rat.

A method of direct percutaneous injection of testosterone (T)-laden microspheres directly into the testis was used in an attempt to achieve the maintenance of normal intratesticular T concentrations, spermatogenesis, and fertility. Rats were divided into three groups: (1) sham operated/injection controls; (2) animals receiving 250 micrograms/d gonadotropin-releasing hormone (GnRH)-antagonist; and (3) animals receiving GnRH-antagonist as in group 1 plus 20 mg T-laden microspheres/testis. Treatment periods were 45 and 90 days. Serum T, testicular interstitial fluid T, testis weights, epididymal weights, daily sperm production (sperm x 10(6)/g/d), cauda sperm motility, and fertility were assessed in all animals. Gonadotropin-releasing hormone antagonist treatment reduced serum and testicular interstitial fluid to below detectable levels at day 45 and to similar levels at day 90. Supplementation with T-laden microspheres maintained testicular interstitial fluid T at concentrations not different from controls without elevation of serum T concentrations. All other values, including fertility were suppressed by GnRH-antagonist treatment and maintained by supplementation with T-laden microspheres.

Animals↗
PubMed1990

Testicular blood flow in peripubertal and older rats with unilateral experimental varicocele and investigation into the mechanism of the bilateral response to the unilateral lesion.

Testicular and reference organ blood flows and testicular temperatures were determined in peripubertal and mature rats with and without experimental left varicocele (ELV). Testicular blood flow and temperature were significantly increased bilaterally 30 days after surgery to induce unilateral varicocele, and this was the case in both the younger and older animals. It has not previously been known that the pathophysiological effects of ELV extended to the peripubertal testis. Previous experiments have demonstrated that the left testis is not necessary for the right testicular response to varicocele. In the present paper, animals were subjected to left orchiectomy simultaneously with the surgery to induce ELV. Thirty days later, the animals were divided into those with and those without the left spermatic vein varicosity. Testicular blood flow was determined in all these animals as well as in a separate group of control and experimental varicocele animals. The group of ELV animals with left spermatic varicosity demonstrated a significant increase in contralateral testicular blood flow while the ELV group without left spermatic varicosity did not. We speculate that left venous distention is involved in the mechanism for the contralateral response to unilateral varicocele.

Animals↗
PubMed1990

Transepithelial movement of non-polar and polar compounds in male rat reproductive tubule examined by in vivo microperifusion and in vivo micropuncture.

Proluminal movement of 3H-testosterone and 3H-sucrose from peritubular to intratubular fluids of the adult rat testis and epididymis was investigated by using in vivo microperifusion and subsequent micropuncture of seminiferous tubules and caput, corpus, and cauda epididymal tubules. Tubules were perifused with Minimum Essential Medium containing 3H-testosterone or 3H-sucrose. 14C-polyethyleneglycol was included in the perifusion fluid as a marker for contamination of intraluminal fluid by interstitial fluid. Radioactivity of isotopes in perifusion and intraluminal fluids was determined at one and two hours after perifusion and the percentage of peritubular isotopes appearing in intraluminal fluid was determined. Net entry of 3H-sucrose into the seminiferous and epididymal tubules was significantly reduced. Proluminal movement of 3H-androgen across the seminiferous epithelium was also restricted. In contrast, intraluminal 3H-androgen concentrations in caput epididymal fluid were 200 to 300% of those in peritubular fluid at both one and two hours after perifusion. Similar results were found in the corpus epididymidis. 3H-androgen concentrations in cauda epididymal fluid were approximately 125% of peritubular isotope concentrations. The exact mechanism underlying this uphill proluminal movement of 3H-androgen into the rat epididymal lumen remains to be elucidated.

Androgens↗
PubMed1990

Intraluminal androgen binding protein alters 3H-androgen uptake by rat epididymal tubules in vitro.

Previous experiments have shown that androgen binding protein (ABP) and androgens exist in high concentrations in the tissue and the lumen of the rat caput epididymis. The present experiments were performed to determine whether or not intraluminal APB affects tubule net uptake of androgens. Caput epididymal tubules were dissected into 2-cm segments, subjected to microperfusion into the tubule lumen, and incubated for 2.5 h in 35 degrees C minimum essential medium (MEM) containing 2.0 ng tritiated testosterone (3H-T) per ml. 14C-polytheylene glycol [PEG] was included as a contamination marker. In the first series of experiments, caput tubules were perfused with a control, artificial perfusion (MKB) containing no ABP or fresh rat rete testis fluid (RTF), which is known to contain ABP. Tubules incubated while containing RTF took up 138% of the tritiated androgens taken up by control tubules. In the second series of experiments, tubules were perfused with fresh caput epididymal lumen content, MKB alone, MKB containing either 5.0 ng purified rat ABP/microliters or 50 ng ABP/microliters. Tubules incubated while containing perfused MKB took up only 47% of the tritiated androgens taken up by tubules containing perfused native lumen content. Increasing intraluminal ABP concentrations in the MKB medium increased 3H-androgen uptake in a stepwise fashion. Intraluminal ABP at a concentration of 50 ng/microliters was associated with a 71% return of 3H-androgen uptake towards that amount of 3H-androgen taken up by tubules perfused with native lumen content. Intraluminal ABP enhances net androgen uptake by caput epididymal tubules from their surrounding medium in vitro.

Androgen-Binding Protein↗
PubMed1989

Cytoskeletal involvement in spermiation and sperm transport.

The process of spermiation and sperm transport was studied using specific inhibitors of cytoskeletal elements. Within 12-24 hr after the intratesticular injection of taxol, a compound that acts to stabilize microtubules and inhibit microtubule-related processes, an unusually large number of microtubules was seen within the body of the Sertoli cell. At the same time, transport of elements within the seminiferous epithelium was affected. At the end of stage VI of the cycle, step 19 spermatids were maintained in the deep recesses of the Sertoli cell and not transported to the rim of the seminiferous tubule lumen. At stage VIII, residual bodies remained at, or near, the rim of the tubule and were not transported to the base of the tubule. They underwent only partial degradation at this site, indicating that there may have been two phases involved in their dissolution--one autophagic and one phagocytic, but the latter did not occur since the residual bodies were not transported to Sertoli lysosomes at the base of the tubule. The observations suggest that microtubules are involved in transport processes within the seminiferous epithelium. Within 1-12 hr after the intratesticular injection of 500 microM cytochalasin D, a compound which interferes with actin-related processes, normal appearing tubulobulbar complexes were not present. The tubular portion (distal tube) of the complex did not initiate development. It was assumed that filaments (which were identified as such using NBD-phallacidin and the S-1 fragment of myosin) played an important role in the development of this portion of the complex. Cells did not eliminate cytoplasm normally, as evidenced by an enlarged cytoplasmic droplet, further emphasizing the published role for tubulobulbar complexes in cytoplasmic elimination. Although sperm were released normally from stage VIII tubules, many remained within the tubular lumen and did not traverse the duct system. Cytochalasin did not inhibit fluid secretion by the Sertoli cell, as demonstrated by efferent duct ligation, but did alter myoid cell actin cytoskeletal organization, suggesting that myoid cell contractility is primarily responsible for transport of sperm. Overall, the observations suggest that cytoskeletal activity of the Sertoli cell is important for several aspects of the spermiation process as well as sperm transport.

Actins↗
PubMed1989

Histologic analysis of orchiopexy in a cryptorchid rabbit model.

Although there is a consensus that very early orchiopexy is advantageous, there is little experimental data to support this view. Therefore, we studied early pre-pubertal versus later pre-pubertal orchiopexy in a cryptorchid rabbit model. Male offspring were divided into four groups with six to nine rabbits in each group: 1) controls (CON); 2) shams undergoing sham operations at both three weeks and two months of life (SHAM); 3) cryptorchid on day 3 with orchiopexy at three weeks and sham operation at two months (O3W); 4) cryptorchid on day 3 with sham operation at three weeks and orchiopexy at two months (02M). All animals were sacrificed post-puberty at six months of age; the tests were fixed in situ by perfusion fixation, embedded in glycol methacrylate, and underwent morphometric analysis in a blinded fashion. The average seminiferous tubular diameter (STD) of the CON, SHAM, O3W, and O2M groups was 234, 160, 116, and 123 microns, respectively. The average testicular biopsy score count (TBSC) of the CON, SHAM, O3W and O2M groups was 9.0, 5.2, 3.5 and 3.5, respectively. There is no significant difference in STD or TBSC between the O3W and O2M cryptorchid groups, and values for both of these groups were significantly different from those of the SHAM group. In addition, a significant effect of sham operation was demonstrated. These results demonstrate no advantage of very early orchiopexy in this model, and are consistent with the clinical literature which, in general, shows reduced reproductive potential of a cryptorchid testis after orchiopexy.

Age Factors↗
PubMed1989

Effects of experimental varicocele require neither adrenal contribution nor venous reflux.

Experimental left varicocele (ELV) is known to induce bilateral changes in the rat testis that, where comparisons are possible, are similar to the changes induced by unilateral varicocele in the human. In the present study, we have determined whether or not left adrenal products are important to the changes induced by ELV and whether or not reflux of left renal vein content occurs in the ELV rat. In the first study, testicular blood flow and temperature were studied in control animals and those with ELV, left adrenalectomy (LAX), or ELV + LAX. Control left and right testicular blood flow (33.6 +/- 0.8 and 33.6 +/- 1.5 ml./min./100 gm. tissue respectively) was significantly elevated by ELV (to 39.9 +/- 0.9 and 41.2 +/- 2.7 ml./min./100 gm. tissue, respectively) and the difference between abdominal and testicular temperatures (delta T) was significantly reduced. Control delta T's for right and left testes were 3.2 +/- 0.2C and 3.2 +/- 0.2C, respectively, and right and left delta T's for ELV animals were 2.0 +/- 0.3 degrees C and 2.0 +/- 0.3C, respectively. These blood flow and temperature changes also occurred when ELV animals were subjected to simultaneous LAX. Additionally, when 85Sr-labelled microspheres were infused into the left renal vein, they did not appear in either left or right testes of ELV animals. We conclude that there is no evidence for reflux down the spermatic vein in ELV in rats and adrenal products do not reach the testis via this route after being secreted into the renal vein. We raise the suggestion that the same may be true in the human.

Adrenal Glands↗
PubMed1989

Sulfated oviductal glycoproteins in the rabbit: quantitation by competitive enzyme-linked immunosorbent assay.

The rabbit oviductal epithelium synthesizes and secretes a family of antigenically related, sulfated oviductal glycoproteins (SOG). Anti-SOG monoclonal antibodies (Mabs) were produced and two (Mab 1 and Mab 2) were selected for further characterization. Periodate oxidation of Western blots of oviductal fluid did not affect the binding of Mab 1 or Mab 2, thus suggesting that these antibodies recognized protein rather than carbohydrate epitopes on SOG. The specificity of Mab 1 was determined by Western blot analysis of tissues obtained from estrous rabbits and from the male rabbit reproductive tract. SOG was identified in tissue extracts of both the oviductal ampulla and isthmus. Cervix was the only non-oviductal tissue with which Mab 1 cross-reacted. Mab 1 was used to isolated SOG from whole oviductal fluid by immuno-affinity chromatography. Affinity-purified SOG and Mab 1 were used to develop a quantitative, SOG-specific, competitive enzyme-linked immunosorbent assay. This assay was used to quantify SOG in rabbit oviductal fluid collected during estrus and pseudopregnancy. SOG secretion during pseudopregnancy was resolved into two transient episodes of increased secretion. Maximum SOG secretion (X = 1039 +/- 199 micrograms/day) occurred within 48 h of the induction of pseudopregnancy. A second period of enhanced SOG secretion (X = 308 +/- 46 micrograms/day) occurred during the fifth and sixth days of pseudopregnancy. Baseline SOG secretion occurred during estrus at approximately 60% of maximum postovulatory secretion.

Animals↗
PubMed1989

Effect of steroid hormones on sulfated oviductal glycoprotein secretion by oviductal explants in vitro.

Explants of rabbit ampullary and isthmic tissue were cultured 4 days with and without exogenous steroids, and the sulfated oviductal glycoprotein (SOG) concentration in the explant culture supernatants was determined. Tissues cultured with progesterone plus estrogen secreted significantly more SOG than control tissues, whereas tissues cultured with estrogen alone did not. Ampullary tissues cultured with progesterone plus estrogen secreted significantly more SOG than control tissues on Days 2 and 3, whereas SOG secretion by isthmic tissues was significantly above control secretion on Day 4. Ampullary and isthmic tissues differed significantly in their secretory capacity. Maximum ampullary SOG secretion was approximately 650 ng SOG/mg tissue/day. Maximum isthmic SOG secretion was approximately 30 ng SOG/mg tissue/day. These findings suggest that the oviduct is composed of discrete functional regions that provide support to gametes and developing embryos through the unique secretory characteristics of each region.

Animals↗