Striated muscles in visceral organs of vertebrates

Abstract

Pathologists involved in the examination of small rodent tissues are familiar with the presence of striated muscle in walls of intrapulmonary veins. Because these striated muscles express cardiomyocyte markers and are involved in rhythmical contraction during systole, this morphologic arrangement was named "pulmonary myocardium". Striated cardiac muscles of intrapulmonary veins have also been found in numerous species, including non-human primates. Great attention has been given to animal striated pulmonary veins because in humans, the presence of cardiomyocytes in the pulmonary veins (myocardial sleeves) is a major origin of paroxysmal atrial fibrillation. It is unequivocally suggested that direct extension/migration of cardiomyocytes from the left atrium into pulmonary veins is the origin of "pulmonary myocardium". This model sounds logical in regard to humans and large mammals because in these cases, striated myocytes extend into pulmonary veins only by 10-30 mm from the left atrium. However, the cardiomyocyte direct extension/migration model becomes less parsimonious when applied to the numerous small intrapulmonary veins with striated muscles in their walls in small mammals. In 1972, Alfred Sherwood Romer, renowned for his contributions to the study of vertebrate evolution, suggested that visceral smooth muscle cells developed a striated phenotype due to the need for more efficient musculature. Romer theorized that the primary anatomical division of the vertebrate muscular system should be not into smooth and striated types but into somatic and visceral systems, because the line of division along the gut between striated and smooth musculature is not a fixed point. Romer's work offered a parsimonious model for the presence of striated muscle in the walls of the intrapulmonary veins-visceral smooth muscle cells, which are capable of differentiating into striated muscle cells, are always present; whether they differentiate depends on functional demands. From Romer's hypothesis, it also could be foreseen that striated muscle could appear in visceral compartments other than the blood circulatory system and pharyngeal muscles to facilitate functional needs. Indeed, it was shown that 1) the lymphatic system of many low vertebrates acquired a lymphatic heart with striated muscle cells; 2) some vertebrates also acquire striated muscles in tunica Muscularis of the stomach and intestine. The facts above undoubtedly corroborate Prof. Romer's notion on the evolution of the vertebrate muscular system.

The villi ileum growth of native quail fed by irradiated chitosan with glutathione from early age in high temperature

“…The results showed a change due to the administration of chitosan with different doses. This supports the statement of [13][14][15] that the administration of chitosan with lower levels shows good anti-inflammatory. [16] reported the effect of giving 150 ppm irradiated chitosan in the diet on the morphometric improvement of the ileum of cihateup ducks.…”

Dried probiotics enhances immunity and liver function of final production laying hens maintained at upper temperatures zone

“…This increase is related to the function of liver cells. It is known that liver cells are responsible for the production of albumin [15][16][17][18][19][20][21][22][23], so the higher the albumin, the higher the plasma total protein levels.…”

“…As for the role of DP administered through feed, several researchers have previously reported that the administration of DP in feed is able to improve the rhythm and rate of metabolism in livestock, and show good physiological responses [17,18,[25][26][27][28][29]. Other researchers have shown that feeding probiotics to animals and livestock has an impact on their biochemical profiles.…”

“…Previous studies have shown that probiotics can act as anti-stress agents, and some previous reports have also shown their effectiveness as antimicrobials and antibiotics, so they are expected to prevent molds and aflatoxins from entering the absorptive cells of the ileum through feed [14]. Immune system stimulation triggered by probiotics can increase immunity-related plasma proteins with 2-4% in animal diet [15][16][17]. This increase in plasma protein is indicated by high production of total protein with fed 4% probiotics [4], albumin and globulin as well as leukocytes and their differentiation [11].…”

Enhancement of the liver status of Sentul chickens from the starter phase induced by irradiated chitosan

“…The provision of chitosan in the ration increases the growth of villi as well as digestibility and absorption of nutrients. Feed with the addition of chitosan stimulates immune function and improves digestion and absorption of nutrients to improve growth performance [30][31][32][33]. It is associated with the risk of reducing liver tissue damage, which is characterized by a decrease in the value of SGPT and SGOT.…”