scholarly journals Cell Fractionation of Anterior Pituitary Glands from Beef and Pig

1959 ◽  
Vol 5 (1) ◽  
pp. 17-23 ◽  
Author(s):  
Frank S. Labella ◽  
J. H. U. Brown
Keyword(s):  
Alkaline Phosphatase ◽  
Anterior Pituitary ◽  
Secretory Granules ◽  
Succinic Dehydrogenase ◽  
Subcellular Fractions ◽  
Acid Proteinase ◽  
Cell Fractionation ◽  
Ph Optimum ◽  
Pituitary Glands ◽  
The Individual

Fresh anterior pituitary glands from beef and pig were separated by differential centrifugation into subcellular fractions. Nuclei and debris were obtained at 700 g for 15 minutes, secretory granules at 7000 g for 20 minutes, mitochondria at 34,000 g for 15 minutes, and microsomes at 78,000 g for 3 hours. Electron micrographs were taken of the individual fractions. Each fraction was analyzed for nitrogen, pentosenucleic acid (PNA), and phospholipide. Beef and pig anterior lobes were quite similar in their intracellular composition as seen in the subcellular fractions. Succinic dehydrogenase was localized in mitochondria, while alkaline phosphatase was concentrated in the microsomes. A proteinase with pH optimum at 8.2 was exclusively localized. in microsomal and supernatant fractions. Acid phosphatase, acid ribonuclease, and acid proteinase were distributed among the subcellular fractions in another pattern, indicating the presence of a particle type distinct from mitochondria and microsomes. The distribution of cytoplasmic PNA paralleled that of alkaline phosphatase.

LOCALIZATION AND CHARACTERIZATION OF CHOLINESTERASE IN SUBCELLULAR FRACTIONS OF RAT BRAIN AND BEEF PITUITARY

1961 ◽  
Vol 39 (9) ◽  
pp. 1335-1345 ◽  
Author(s):  
Surendra S. Parmar ◽  
Morley C. Sutter ◽  
Mark Nickerson
Keyword(s):  
Rat Brain ◽  
Cholinesterase Activity ◽  
Succinic Dehydrogenase ◽  
Anterior Lobe ◽  
Subcellular Fractions ◽  
Posterior Pituitary ◽  
Low Concentrations ◽  
Pituitary Glands ◽  
Hydrolysis Of

Fresh rat brains and fresh anterior and posterior pituitary glands of beef were separated by differential centrifugation into subcellular fractions, characterized on the basis of sedimentation and succinic dehydrogenase activity. Cholinesterase activity was measured by both manometric and colorimetric methods, the results of which were comparable. Cholinesterase activity of rat brain was found mainly in the microsome and supernatant fractions. It was quite uniformly distributed in all subcellular fractions of both anterior and posterior pituitary. Comparisons of the relative rates of hydrolysis of acetylthiocholine and butyrylthiocholine, and of inhibition by eserine, indicated that brain contains a much higher percentage of acetylcholinesterase than do both lobes of the pituitary, which contain relatively low concentrations of the specific enzyme. Total cholinesterase activity and its sensitivity to inhibition by eserine in the posterior pituitary were found to be midway between those of the anterior lobe and of the brain, from which the posterior pituitary was derived during embryological development.

scholarly journals LYSOSOME FUNCTION IN THE REGULATION OF THE SECRETORY PROCESS IN CELLS OF THE ANTERIOR PITUITARY GLAND

1966 ◽  
Vol 31 (2) ◽  
pp. 319-347 ◽  
Author(s):  
Robert E. Smith ◽  
Marilyn G. Farquhar
Keyword(s):  
Anterior Pituitary ◽  
Dense Body ◽  
Secretory Granules ◽  
Secretory Process ◽  
Secretory Cells ◽  
Residual Body ◽  
Multivesicular Bodies ◽  
Dense Bodies ◽  
Pituitary Glands ◽  
Secretory Products

The nature and content of lytic bodies and the localization of acid phosphatase (AcPase) activity were investigated in mammotrophic hormone-producing cells (MT) from rat anterior pituitary glands. MT were examined from lactating rats in which secretion of MTH1 was high and from postlactating rats in which MTH secretion was suppressed by removing the suckling young. MT from lactating animals contained abundant stacks of rough-surfaced ER, a large Golgi complex with many forming secretory granules, and a few lytic bodies, primarily multivesicular bodies and dense bodies. MT from postlactating animals, sacrificed at selected intervals up to 96 hr after separation from their suckling young, showed (a) progressive involution of the protein synthetic apparatus with sequestration of ER and ribosomes in autophagic vacuoles, and (b) incorporation of secretory granules into multivesicular and dense bodies. The content of mature granules typically was incorporated into dense bodies whereas that of immature granules found its way preferentially into multivesicular bodies. The secretory granules and cytoplasmic constituents segregated within lytic bodies were progressively degraded over a period of 24 to 72 hr to yield a common residual body, the vacuolated dense body. In MT from lactating animals, AcPase reaction product was found in lytic bodies, and in several other sites not usually considered to be lysosomal in nature, i.e., inner Golgi cisterna and associated vesicles, and around most of the immature, and some of the mature secretory granules. In MT from postlactating animals, AcPase was concentrated in lytic bodies; reaction product and incorporated secretory granules were frequently recognizable within the same multivesicular or dense body which could therefore be identified as "autolysosomes" connected with the digestion of endogenous materials. Several possible explanations for the occurrence of AcPase in nonlysosomal sites are discussed. From the findings it is concluded that, in secretory cells, lysosomes function in the regulation of the secretory process by providing a mechanism which takes care of overproduction of secretory products.

scholarly journals ISOLATION AND BIOLOGICAL PROPERTIES OF SECRETORY GRANULES FROM RAT ANTERIOR PITUITARY GLANDS

1969 ◽  
Vol 43 (3) ◽  
pp. 564-574 ◽  
Author(s):  
Allen Costoff ◽  
W. H. McShan
Keyword(s):  
Electron Microscopy ◽  
Anterior Pituitary ◽  
Close Agreement ◽  
Secretory Granules ◽  
Cell Types ◽  
Pituitary Hormones ◽  
Biological Properties ◽  
Single Fraction ◽  
Rat Pituitary ◽  
Pituitary Glands

A method is described for the isolation of secretory granules from rat anterior pituitary glands. The method consists of differential and isopycnic gradient centrifugations, followed by filtration of the zones containing granules on Nuclepore filters to remove mitochondria. Highly purified granules were obtained as indicated by electron microscopy. Major parts of the thyrotropin (TSH) and adrenocorticotropin (ACTH) were recovered in a single fraction of granules as were follicle-stimulating (FSH) and luteinizing (LH) hormones. The somatotropin (STH) and prolactin (LTH) were recovered in separate granule fractions. The major parts of the six different hormones were associated with their respective granule fractions as shown by bioassays specific for each of the hormones. The diameters of granules in sections of intact rat pituitary glands and in isolated pellets were measured, and the means and ranges were in close agreement. These results contribute to the identification of the cell types which produce the different pituitary hormones.

scholarly journals Diabetes and Hypercholesterolemia Impair the Cytological Structure of the Anterior Pituitary Gland

2019 ◽  
Vol 16 (3) ◽  
pp. 649-658
Author(s):  
Ahmed MR Abdo ◽  
Mohamed E El-Beeh ◽  
Sameer H. Qari ◽  
Dina A El-badry ◽  
Hassan IH El-Sayyad
Keyword(s):  
Body Weight ◽  
Pituitary Gland ◽  
Anterior Pituitary ◽  
Secretory Granules ◽  
Reproductive Function ◽  
Anterior Lobe ◽  
Anterior Pituitary Gland ◽  
Albino Rats ◽  
Pituitary Glands ◽  
Cytological Picture

Increase consumption of high fat diet was found to alter blood sugar level similar to diabetes and contributed to the development of obesity and affected the reproductive function of both sexes. The study aimed to clarify the influence of diabetes and or hypercholesterolemia on the cytological picture of cells of the anterior lobe of pituitary gland of male albino rats. Eighteen male albino rats weighing approximately 120 gram body weight were divided into three main groups; control, diabetes, hypercholesterolemia, diabetes (single i.p. 40 mg streptozotocin/kg B.wt plus 100mg. nicotinamide /kg body weight) and hypercholesterolemia (diet containing 3% cholesterol). Dietary feeding on cholesterol and diabetes were carried out for 12 weeks. At the end of treatment, animals were sacrificed, and pituitary glands were separated and their anterior lobe was processed for cytological investigations by transmission electron microscopy. The present study revealed that the rats subjected to experimental diabetes and/ or hypercholesterolemia exhibited a decrease of the secretory granules within the gonadotroph cells somatotroph and corticotrophin cells. There was a detected intracellular accumulation of fat globules in both the gonado- and sommatotroph cells. The authors reported that the altered cytological structures of the secretory function of the anterior pituitary gland led to marked impairment of the male hormonal level and causing infertility.

scholarly journals Ultrastructural localization of prolactin in the rat anterior pituitary glands by preembedding peroxidase-labeled antibody method: observations in normal, castrated, or estrogen-stimulated specimen.

1982 ◽  
Vol 30 (9) ◽  
pp. 919-925 ◽  
Author(s):  
R Y Osamura ◽  
N Komatsu ◽  
S Izumi ◽  
S Yoshimura ◽  
K Watanabe
Keyword(s):  
Anterior Pituitary ◽  
Secretory Granules ◽  
Ultrastructural Localization ◽  
Pronounced Increase ◽  
Alternative Pathways ◽  
Antibody Method ◽  
Pituitary Glands ◽  
Normal Rat ◽  
Estrogen Stimulation

Ultrastructural localization of prolactin (PRL) was studied immunocytochemically (preembedding peroxidase-labeled antibody method) in a variety of pituitaries, including those from 1) normal, 2) castrated, and 3) castrated and estrogen-stimulated rats. In the normal rat, PRL was observed in cisternae of the rough endoplasmic reticulum (RER), perinuclear spaces, Golgi saccules, and secretory granules. In the castrated rats, PRL cells were rather atrophic and were filled with many small PRL-positive secretory granules. RER and Golgi saccules were rather inconspicuous and were almost devoid of PRL localization. The serum PRL level was markedly lowered. With estrogen stimulation after castration, the serum PRL level was markedly elevated and PRL cells showed a pronounced increase of PRL filled cisternae in the RER. From these observations, the role of secretory granules, Golgi apparatus, and RER in hormonal secretion was defined, and it was postulated that some peptide hormones would be secreted along two alternative pathways, i.e., either 1) a long (regulated) pathway or 2) a short (accelerated) pathway, in accordance with their secretory activities, which could be altered by various stimulations such as the use of estrogen.

ANALYSIS OF DIAMETERS OF HUMAN PITUITARY HORMONE SECRETORY GRANULES

1977 ◽  
Vol 85 (2) ◽  
pp. 249-255 ◽  
Author(s):  
A. B. Gray
Keyword(s):  
Electron Micrographs ◽  
Anterior Pituitary ◽  
Secretory Granules ◽  
Pituitary Hormone ◽  
Human Pituitary ◽  
Pituitary Glands ◽  
The Mean ◽  
Human Anterior Pituitary

ABSTRACT Measurements were made on electron micrographs of six human anterior pituitary glands of the maximal diameters of secretory granules in 130 cells, average 91 granules per cell. This was done in an attempt to classify the various hormone types solely by differences in the mean diameters of the secretory granules. The range of diameters in nanometers could be segregated into six subgroups of the following suggested functions: 135.5 ± 13.6 TSH, 181.6 ± 9.3 LH, 226.0 ± 19.4 FSH, 356.8 ± 30.5 ACTH/MSH, 452.9 ± 23.8 GH, 559.9 ± 38.0 prolactin.

scholarly journals ISOLATION AND BIOCHEMICAL STUDY OF SECRETORY GRANULES FROM RAT PITUITARY GLANDS

1962 ◽  
Vol 15 (2) ◽  
pp. 159-172 ◽  
Author(s):  
J. F. Perdue ◽  
W. H. McShan
Keyword(s):  
Alkaline Protease ◽  
Density Gradient Centrifugation ◽  
Biochemical Study ◽  
Secretory Granules ◽  
Gradient Centrifugation ◽  
Succinic Dehydrogenase ◽  
Acid Protease ◽  
Alkaline Phosphatases ◽  
Rat Pituitary ◽  
Pituitary Glands

Secretory granules from anterior pituitary glands of young adult male castrate rats were isolated by differential centrifugation, microfiltration, and discontinuous density gradient centrifugation. The granules were obtained as pellets, sectioned, and studied with the electron microscope. A major part of the gonadotropin and a substantial amount of the TSH were associated with the isolated granules. Negligible amounts of growth hormone and prolactin were present as contaminants. Succinic dehydrogenase, glucose-6-phosphatase, acid protease, and acid and alkaline phosphatases were not found in the granules. Alkaline protease was the only enzyme found to be associated with the granules, and it is suggested, in the light of these results, that the alkaline protease may be involved in the release of the hormones.

Sign in / Sign up

Export Citation Format

Share Document