Age related changes in the rat adrenal gland during prenatal period; [study-1]

Adrenals are complex and important glands of dual character in mammals. The growth of the rat adrenal gland is relatively slower than the general body growth. To observe the age related changes in the adrenal gland of the albino rat during prenatal period. SETTING: Albino rats used were obtained from Animal House of BMSI, JPMC, Karachi. Twenty four fetuses of 15,17,19 and 21 days of gestation were used by dividing into four groups [A to D] each composing 6 fetuses. METHODS: Right adrenals were dissected free, fixed and then stained with 1% toluidine blue solution to study under light microscope. Were dissected free, fixed and then stained with 1% toluidine blue solution to study under light microscope. RESULTS AND CONCLUSIONS: The adrenals showed continuous growth throughout the study. The pancenchymal zonation of cortex started on 15th day and developed on 21st day. In all the cortical zones, the predominance of desk cells over the light cells was observed irrespective of age group studied. The mitotic activity was maximum at the time of birth in both the zones of cortex. The lipid globules in the cortex started developing on 21st day. The medulla appeared distinctly on the 19th day. Both myelinated and unmyelinated nerve fibers were observed in between the cortical cells traversing the whole thickness of cortex from capsule to the medulla

fibre size of the hindlimb nerves and their roots in albino rat

OBJECTIVE: To estimate the number and diameters of myelinated fibres in the tibial nerve[TN]; common peroneal nerve[CPN] and their dorsal and ventral roots L4, L5 and L6 in albino rat. SETTING: Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi. SUBJECT: Male adult albino rats. Period: One year. MATERIAL AND METHODS: The number and diameters of myelinated fibres were estimated from the photomicrographic montages of their araldite embedded transverse sections. The mean count of myelinated fibres in TN was more than CPN while their population in both the dorsal and ventral roots of L5 segment outnumbered the other two segments. The mean diameters of myelinated fibres forming TN and CPN ranged between 2.3-12.2 [micro]m and 2.4-12 [micro]m respectively, while their dorsal and ventral roots measured between 1-12 [micro]m and 2-14 [micro]m. A decrease in the fibre size in both the nerve roots occurred rostrocaudally, however, the size range in the ventral roots appeared to be larger than in the dorsal roots whereas the CPN has slightly more larger sized fibres than the TN

Distribution of epidermal melanin pigment among the inhabitants of Karachi

A study was conducted at Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre [JPMC] Karachi, to investigate the distribution of epidermal melanin with respect to age and ethnic groups in Pakistan and intensity of epidermal melanin under ultraviolet radiation among the inhabitants population of Karachi. Epidermal malanin in 5 micro m thick vertical paraffin embedded sections of eighty human skin samples were studied with light microscopy from different age and ethnic groups with schmort technique. The quantity of epidermal melanin diminished as the age advanced. There was no significant difference among different ethnic groups in Pakistan, and the amount of epidermal melanin was significantly higher in exposed than in unexposed parts of body among the population of Karachi. The distribution of epidermal melanin appeared to be inversely proportional to the advancing age, it remained constant among different ethnic groups of Pakistan, but the intensity was significantly higher in exposed than in unexposed parts of body among Karachiites

Study of myelinated fibers in the common peroneal nerve in monkey

The common peroneal nerve [CPN] motoneurons were localized by horseradish peroxidase neuronal tracing technique. They extended from caudal part of L4 to the caudal part of L6 segments of the spinal cord in monkey [macaca mulatta]. The number and diameters of myelinated fibres in the CPN and its ventral roots, L4, L5 and L6 of the monkey were estimated from the photomicrographic montages of their araldite embedded transverse sections. The mean count of these fibres was 896 in L4, 3228 in L5, 6959 in L6 and 7497 in CPN. The average diameters of myelinated fibres in ventral root measured between 2 and 1 [micro]m and in CPN between 2 and 22 [micro]m. The percentage of myelinated fibres measuring 9 [micro]m and above was 79.1% in L4, 86.7% in L5, 63.4% in L6 and 63.5% in common peroneal nerve

Visualization of neurons forming the obturator nerve in albino rat

To localize and estimate the size, number and segmental distribution of motor, dorsal root ganglion [DRG] and postganglionic sympathetic [PSN] neurons whose axons form the obturator nerve in albino rat. Setting: Department of Anatomy, Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi. Subjects: Male, adult albino rats of Charles River strain. Main outcome measures: Horseradish peroxidase [HRP] method of tracing neurons by injecting 25-30% HRP solution into the muscles supplied by the obturator nerve. The motoneurons extended between L2 and L4 segments of the spinal cord, appeared as groups of neurons occupying anterolateral, posterolateral and central groups. The labelled sensory neurons located in L2-L4 ipsilateral dorsal root ganglia were densely populated in L3 DRG without any somatotopic organization. Ike sympathetic neurons were labelled in L2-L4 sympathetic ganglia with heavy labelling in The. The somal diameters of the motoneurons ranged between 10 and 50 micro m with majority having somal diameters greater than 25 micro m. The size spectrum of sensory neurons measured between 12 and 50 micro m and that of sympathetic ganglion cells between 10 and 38 micro m

Study of motor units innervated by common peroneal nerve in monkey

The average number and size of motor units were assessed by investigating the components of motor units supplied by Common Peroneal Nerve in monkey [macaca mulatta]. The motoneurons forming the common peroneal nerve [CPN] localized by horseradish peroxidase neuronal tracing technique extended from the caudal part of L[4] to the caudal part of L[6] segments of the spinal cord. The average somal diameter of motoneurons ranged between 14 and 78 m. The motoneurons measuring more than 38 [micro]m [presumably the alpha neurons] were 69.23%. The motor end-plates on skeletal myofibres of muscles supplied by the CPN were localized by using Bromo-indigo and urea-silver technique. The average number of motor units was assessed as the ratio between the number of motoneurons and the motor endplates. The total of 992 motor units with the size of 157 of the muscles innervated by the CPN have been observed in the present study

Localization of motor, sensory and postganglionic sympathetic neurons forming the femoral nerve in albino rat

The present study yields informations on the location, number and size of motor, sensory and postganglionic sympathetic neurons forming the femoral nerve in albino rats localized by horseradish peroxidase [HRP] method of tracing neuronal connections. It showed that the motoneurons of femoral nerve extended between L[1] and L[4] segments of the spinal cord. They appeared as groups of neurons occupying anterolateral, posterolateral and central groups. The labeled sensory neurons were located in L[1] - L[4] dorsal root ganglia[DRG] and were concentrated mostly in L[3] DRG with no somatotopic organization of the cells. The postganglionic sympathetic neurons [PSN] were labeled in L[1] - L[4] sympathetic ganglia with peak frequency in L[4] sympathetic ganglion. The somal diameters of motoneurons forming the femoral nerve ranged between 10 and 58 [micro]m with majority having somal diameters greater than 25 [micro]m. The size spectrum of sensory neurons measure between 14 and 60 [micro]m. The sympathetic neurons measure between 10 and 44[micro]m

Age related changes in the rat adrenal cortex

The present study revealed that the growth of the rat adrenal gland was relatively slower than general body growth. However, growth of the cortex preceded that of the medulla. The parenchyma showed three usual zones but a fourth inconstant lipid-poor, zona intermedia between outer glomerulosa and middle fasciculata was also observed. In all cortical zones, the predominance of dark cells over the light cells occurred irrespective of the age groups studied. The advancing age replaced capsular cellular elements with fibrous ones whereas the mitotic activity of the parenchymal cells decreased and an increase in the intracellular lipid in the outer and ascorbic acid in the inner cortex was observed. The glycogen which was restricted mainly to the inner cortex remained unaffected by aging process while the acid phosphatase activity from the inner reticularis extended to the outer cortex in aged group

effect of paracetamol on naprosyn induced damage to gastric mucosa in albino rat

The effect of paracetamol against ulcerogenic agent, naprosyn on the gastric mucosa of albino rat was observed under dissecting as well as laboratory microscope. Paracetamol in a dose of 250 mg/kg body weight provided protection against the ulcerogenic effect of naprosyn under dissecting microscope. Under laboratory microscope, a significant increase in the mucosal thickness with the administration of paracetamol followed by naprosyn was observed, while the flattening of the surface epithelium with slight exfoliation may be attributed to relative increase of pepsin from the chief cell. The increased secretory activity of the mucous neck cells in animals treated with paracetamol followed by naprosyn may be due to the increased bio-synthesis of prostaglandin from these cells which might have produced protective influence against the damaging effect of naprosyn

Measurements of the normal adult lumbar spinal canal

To assess the normal dimensions of the lumbar spinal canal, 100 normal healthy subjects of either sex between 25 and 45 years age were x-rayed for lumber vertebral column in both posteroanterior and lateral views and the canal was measured by Jones and Thomson method1. The lumbar spinal canal showed constant dimensions in both sexes in all age groups when studied separately in the male and female subjects. However, no change in relative dimensions was observed between 25 and 45 years. The canal showed gradual decrease in measurement from L1 to L5 vertebral levels in both sexes but relative width of the canal was more in the females than in the males of the same age group. The normal values of the canal to vertebral body ratio [C/B] varies between 1:2.0 and 1:5.0. The ratio 1:2.0 indicates a wider canal whereas any ratio beyond 1:5.0 would be conclusive of stenosis of the lumbar vertebral canal