Anatomy of parotid gland and its secretory ducts in sheep

Background: The parotid gland in sheep ends freely in front of the masseter muscle, and paracondylary section of occipital bone and extends deep until pterygoid extends of sphenoid bone and hyoid bone. The structure of salivary glands in mammals has been thoroughly studied using histological and sialographic method. This study aimed to reveal the detailed anatomic features and race-specific differences of the canal system of the parotid glands in Akkaraman sheep by using the corrosion cast technique. Materials and methods: Thirteen sheep parotid glands from 7 Akkaraman sheep were used in this study. Parotid glands were removed from their places with ducts. Measurements were made with a calliper from back to front, top to bottom and inside to outside. After dissection of the parotid glands, their volumes were measured according to the ‘Archimedes principle’. Also, 13 sheep parotid glands were examined using the polyester resin method. Results: In the present study, our average metric results were: length of parotid duct was 10.92 ± 1.027 cm, length of parotid gland was 5.87 ± 1.04 cm, volume of parotid gland was 12.50 ± 2.48 cm3, thickness of parotid gland was 0.75 ± ± 0.36 cm and width of parotid gland was 4.07 ± 0.43 cm. The average weight of the parotid gland of Akkaraman sheep was identified as 25.3 g. Accessory parotid gland was not encountered in the current study. Conclusions: It was observed that polyester entered into the parotid duct and filled up until the acinus and made both acinus and secretory ducts well-examined in this study. It was also observed that the parotid gland consisted of lobes and lobules. The average number of lobes was 12. The number of lobules in a lobe varied between 3 and 16, each lobe consisted of an average of 9 lobules. It was found that each lobe has its own lobar duct. Copyright © 2022 Via Medica

The morphology of the afferent and efferent domain of the sheep glomerulus

Background: It is important to know the morphology of the glomerulus in order to explain kidney infiltration. The present study aims to research the morphology of afferent and efferent domains of sheep kidney glomeruli. Materials and methods: In this study, 2000 glomeruli from 20 kidneys of Akkaraman sheep were examined using the polyester resin method. Results: It was found that the glomeruli of sheep kidney usually have an afferent arteriole as well as an efferent arteriole. Besides, it was also found that five glomeruli have two efferent arterioles. It is known that the afferent domain constitutes the largest part of the glomerulus. In two of the glomeruli that we examined, the afferent domain forms the ½ of the glomeruli wherein the other two glomeruli afferent domain forms the ¾. Conclusions: It is known that there are many anastomoses between the afferent and efferent domain capillaries. However, it is not well-explained how anastomosis is created between the afferent and efferent domains. In our study, it was identified that those anastomoses are not inside the lobes but between the surrounding capillaries

A golden ratio for foramen magnum: an anatomical pilot study

Background: The foramen magnum (FM) is an important landmark because of its close relationship to key structures such as the brainstem and spinal cord, an extension of the medulla oblongata. Because of the similarity in their shape, the existence of a relationship between cranial length and anteroposterior diameter of the FM, and between cranial width and transverse diameter of the FM may reveal the magnificent harmony of the skull and FM. Based on this idea, we investigated the existence of this harmony in skulls that we used in our study. Materials and methods: In this study, 60 adult dry skulls belonging to the Turkish population were examined. The anteroposterior and transverse diameters of the foramen magnum and the length and width of the skull were measured. Measurements were made directly on the skull using a digital sliding caliper. New indices and ratios were applied with those measurements. Results: Our study suggests that FM width and FM length could be estimated by using the cranial length and cranial width measurements in the skull by accepting the mean of these coefficients (4.62) as the golden ratio. The average of the coefficients of cranial width to FM width ratio [4.62 ± 0.35 (95% CI: 4.52-4.70)] and the average of the coefficients of cranial length to the FM length ratio [4.62 ± 0.50 (95% CI): 4.49-4.76)] were found to be equal to each other. In order to check the accuracy of this hypothesis, FM width and FM lengths were estimated with the help of new equations. Conclusions: In the present study, the ratio between the anteroposterior and transverse diameters of both FM and the cranium was estimated at 4.62, indicating a magnificent harmony between cranial and subcranial structures. With this ratio, it is easy to estimate FM's size based on simple cranial measurements

Anatomy of parotid gland and its secretory ducts in sheep

Background: The parotid gland in sheep ends freely in front of the masseter muscle, and paracondylary section of occipital bone and extends deep until pterygoid extends of sphenoid bone and hyoid bone. The structure of salivaryglands in mammals has been thoroughly studied using histological and sialographic method. This study aimed to reveal the detailed anatomic features and race-specific differences of the canal system of the parotid glands in Akkaraman sheep by using the corrosion cast technique.Materials and methods: Thirteen sheep parotid glands from 7 Akkaraman sheep were used in this study. Parotid glands were removed from their places with ducts. Measurements were made with a calliper from back to front, top to bottom and inside to outside. After dissection of the parotid glands, their volumes were measured according to the ‘Archimedes principle’. Also, 13 sheep parotid glands were examined using the polyester resin method.Results: In the present study, our average metric results were: length of parotid duct was 10.92 ± 1.027 cm, length of parotid gland was 5.87 ± 1.04 cm, volume of parotid gland was 12.50 ± 2.48 cm3, thickness of parotid gland was 0.75 ± 0.36 cm and width of parotid gland was 4.07 ± 0.43 cm. The average weight of the parotid gland of Akkaraman sheep was identified as 25.3 g. Accessory parotid gland was not encountered in the current study.Conclusions: It was observed that polyester entered into the parotid duct and filled up until the acinus and made both acinus and secretory ducts well-examined in this study. It was also observed that the parotid gland consisted of lobes and lobules. The average number of lobes was 12. The number of lobules in a lobe varied between 3 and 16, each lobe consisted of an average of 9 lobules. It was found that each lobe has its own lobar duct

Vitamin D protects against hippocampal apoptosis related with seizures induced by kainic acid and pentylenetetrazol in rats

Objectives: The hippocampus is susceptible to damage in patients with epilepsy and in animals with seizures caused by excitotoxic agents. The effect of vitamin D on hippocampal apoptosis related with seizures has not been reported. However, epileptic patients have an increased risk of hypovitaminosis D which is most likely due to the effects of antiepileptic drugs. Therefore, in this study, it was aimed to evaluate the effects of vitamin D on hippocampal apoptosis related with seizures by using pentylenetetrazol (PTZ) and kainic acid (KA) in rats. Methods: Male Sprague Dawley rats, aged 5.5 weeks, were randomly divided into six groups: control, vitamin D, PTZ, KA, PTZ + vitamin D and KA + vitamin D groups. The groups that received vitamin D were given 500 IU/kg of vitamin D daily for two weeks in addition to a standard diet. At the end of this period, PTZ and KA were applied to trigger seizures in the rats in the seizure groups. 24 h after the administration of PTZ and KA, the rats were decapitated. In the hippocampal region, apoptosis was assessed by TUNEL and brain-derived neurotrophic factor (BDNF), Bax, caspase-3 and c-fos activation were evaluated by immunohistochemical method. Results: BDNF level increased while c-fos, Bax and caspase-3 levels decreased (p < 0.0001, in all) in the hippocampal neurons of the groups that were pre-treated with vitamin D before the administration of PTZ and KA, in comparison with the PTZ and KA groups. Vitamin D significantly decreased the number of apoptotic cells in these rats in comparison with the PTZ and KA groups (p < 0.0001). Conclusion: This study indicates that vitamin D has neuroprotective effects on hippocampal apoptosis induced by PTZ and KA in rats. With this study it is suggested that keeping vitamin D levels within normal limits may be beneficial for patients with epilepsy, especially children. © 2018 Elsevier B.V