Biomedical subjects

J B Warchol

Publications and source records attributed to J B Warchol.

At least 37 records · Page 2Linked to original sources

PubMed1978

Coated vesicles in the rat anterior pituitary gland.

Ultrastructural documentation of the formation of coated vesicles in prolactin cells of the rat anterior pituitary gland is presented. Coated vesicles were observed forming from the secretory granular membrane in the Golgi area and between the Golgi complex and the plasmalemma. They were also found budding off the membrane lining the exocytotic pocket. Following peroxidase reaction product could be seen forming from the membrane of the exocytotic pocket and adjacent to it. These vesicles were found in transit towards the Golgi area or within lysosomes. It is proposed that these coated vesicles are important for membrane conservation and that this is occurring in developing secretory granules near the Golgi complex, in more mature secretory granules and at the level of the plasmalemma during exocytosis.

Animals↗

PubMed1976

Glycoproteins in membranes of secretory granules of the anterior pituitary gland.

Rat anterior pituitary glands were examined by electron microscopy after staining with five different histochemical stains. Histochemical reactions were observed in the cell coat, cell membrane and the membrane surrounding the secretory granules in all anterior pituitary cells following staining with phosphotungstic acid (PTA), chromic acid and PTA, the periodic acid-thiosemicarbazide-silver protein method (PA-TSC-SP) of Thiéry, ruthenium red and concanavalin A. The staining was abolished when the sections were preincubated with pronase, neuraminidase or trypsin and subsequently exposed to PTA, chromic acid and PTA or PA-TSC-SP. The possible functional role of the glycoproteins present in the membrane surrounding the secretory granules is considered.

Animals↗

PubMed1976

A new method for evaluation of karyometrical measurements.

From karyometrical measurements performed by us and from investigations of other authors it results that the obtained values of nuclear volumes are smaller than real ones. This is caused by different sectioning planes of measured nuclei. Previously published corrections seem not to reflect the real error as they are based on the analysis of the circle, and not of the sphere. In the presented paper a method is given, which may be applicated to interpretation of the results of morphometrical measurements. The proposed method is based on the well known in statistical analysis 3o rule. The obtained results were applicated to a practical example.

Animals↗

PubMed1976

Some aspects of the kinetics of emiocytosis in prolactin cells.

Some aspects of the kinetics of emiocytosis of secretory granules were investigated in pituitary prolactin cells of lactating female rats. Most of the emiocytotic events were directed towards those areas of the cells which were covered with a basal lamina. Diameters of the secretory granules within the emiocytotic pockets and of the openings of the pockets to the exterior were measured. An inverse relationship between the size of the granule and the diameter of the foramen was noted. A mechanism is proposed relative to the processes involved in the release of secretory granules from prolactin cells.

Animals↗

PubMed1975

Distribution of microtubules in prolactin cells of lactating rats.

The intracellular distribution of microtubules was studied using serial sections of prolactin cells in anterior pituitary glands from lactating rats. Numerous microtubules were present in these cells following fixation with glutaraldehyde and osmium tetroxide. The greatest number of microtubules were present in the Golgi complex, situated around the perimeter and in association with the cisternae, vesicles and developing secretory granules. Microtubules were found in channels between groups of parallel cisternae of rough surfaced endoplasmic reticulum and in close proximity to small vesicles. They were also located adjacent to mitochondria, the plasmalemma, the nuclear envelope, and among mature secretory granules. Due to their orientation within the cell, it is suggested that the microtubules may act to direct the movement of organelles from one region of the cell to another and to give internal support to the cell.

Animals↗

PubMed1974