Exocrine gland

Prostate gland. One of the male exocrine glands responsible for secreting seminal fluid. 

Peripheral mAChRs are known to mediate the well-documented actions of ACh at parasympathetically innervated effector tissues (organs) including heart, endocrine and exocrine glands, and smooth muscle tissues [2, 4]. The most prominent peripheral actions mediated by activation of these receptors are reduced heart rate and cardiac contractility, contraction of... 

CP-channels with even smaller conductance have been described for the lacrimal and other exocrine glands [76,77]. These channels have a conductance of 1-2 pS. Unlike the ICOR-channel they appear to be blocked by millimolar concentrations of furosemide [77]. Most recent and only partially published data from my own laboratory obtained with the above modified nystatin technique [50,133,134] indicate that the respiratory epithelial cells and colonic carcinoma cells possess these types of small CP channels, and that these channels are involved in hormonal regulation of CP-conductance (cf. section 5). These CP-channels are regulated by cytosolic Ca. Hormonally induced increases in cytosolic Ca lead to an abrupt increase in the probability of these small CP-channels being open, yet they have no effect on the ICOR-channel. Data of this kind reinforce that the physiological importance of these small CP-channels may have been grossly underestimated. 

O In CF, the cystic fibrosis transmembrane regulator (CFTR) chloride channel is dysfunctional and usually results in decreased chloride secretion and increased sodium absorption, leading to altered viscosity of fluid excreted by the exocrine glands and mucosal obstruction. 

The pancreas is a gland in the abdomen lying in the curvature of the stomach as it empties into the duodenum. The pancreas functions primarily as an exocrine gland, although it also has endocrine function. The exocrine cells of the pancreas are called acinar cells. They produce an alkaline fluid known as pancreatic... 

The autonomic nervous system (ANS), also known as the visceral or involuntary nervous system, functions below the level of consciousness. Because it innervates cardiac muscle, smooth muscle, and various endocrine and exocrine glands, this nervous system influences the activity of most of the organ systems in the body. Therefore, it is evident that the ANS makes an important contribution to the maintenance of homeostasis. Regulation of blood pressure gastrointestinal responses to food contraction of the urinary bladder focusing of the eyes and thermoregulation are just a few of the many... 

The pancreas is an exocrine gland and an endocrine gland. The exocrine tissue produces a bicarbonate solution and digestive enzymes. These substances are transported to the small intestine where they play a role in the chemical digestion of food. These functions are fully discussed in Chapter 18 on the digestive system. 

Exocrine glands within the pancreas secrete an aqueous fluid referred to as pancreatic juice. This fluid is alkaline and contains a high concentration of bicarbonate ion it is transported to the duodenum by the pancreatic duct. 

Probably the best-studied communication behavior in ants is chemical communication, but other sensory modalities, such as mechanical cues, also play an important role in the formation of multicomponent signals in ant communication. Chemical releasers are produced in a variety of exocrine glands, and considerable progress has been made in chemically identifying many of these glandular secretions (for reviews see refs. 1 and 2). In this essay I will not emphasize, however, the natural product chemistry of ant pheromones, but rather concentrate on the proposition that communication in ant societies is often based on multicomponent signals, on nested levels of variation in chemical and other cues, which feature both anonymous and specific characteristics (3). 

Many anthicid species are known to be canthariphilous [121]. After take up, males store the toxin in the accessory glands and transfer it as a kind of nuptial gift to the females. Many male anthicid species are characterized by ely tral exocrine glands which serve for excretion of cantharidin depending on the cantharidin titre. Similar to Pyrochroidae (see there) females test the cantharidin load of males before copulation and select those males which previously were able to incorporate this precious defensive compound from exogenous sources. 

If many unpalatable Lepidoptera obtain their defensive quality by sequestering plant-derived substances, various caterpillars fortify their bodies with spines and hairs containing various toxins [167]. Defensive secretions in specialized exocrine glands were also reported [150-152]. 

Abstract Progress that has been made in research on the chemical aspects of mammalian semiochemistry over the past decade is discussed on the basis of examples from the most topical problem areas. The chemical characterization of the volatile organic constituents of the urine, anal gland secretions and exocrine gland secretions of rodents, carnivores, proboscids, artiodactyls and primates, and their possible role in the semiochemical communication of these mammals are discussed, with particular emphasis on the advances made in the elaboration of the function of proteins as controlled release carrier materials for the semiochemicals of some of these animals. 

Cystic fibrosis (CF) is a hereditary disease of abnormal fluid secretion. It affects cells of the exocrine glands, such as intestine, sweat glands, pancreas, reproductive tract, and especially the respiratory tract. The disease affects about 1 in 2500 infants of the Caucasian population to varying degrees of seriousness. Patients produce thickened mucus that is difficult to get out of the airway. This leads to chronic lung infection, which progressively destroys pulmonary function. 

CF is caused by the absence of a protein called cystic fibrosis transmembrane conductance regulator (CFTR). This protein is required for the transport of chloride ions across cell membranes. On the molecular level, there is a mutation in the gene that encodes for CFTR. As a result, CFTR cannot be processed properly by the cell and is unable to reach the exocrine glands to assume its transport function. 

The side effects of tricyclic antidepressants are largely attributable to the ability of these compounds to bind to and block receptors for endogenous transmitter substances. These effects develop acutely. Antagonism at muscarinic cholinoceptors leads to atropine-like effects such as tachycardia, inhibition of exocrine glands, constipation, impaired micturition, and blurred vision. 

Pharmacology Calcium is essential for the functional integrity of the nervous and muscular systems, for normal cardiac contractility and the coagulation of blood. It also functions as an enzyme cofactor and affects the secretory activity of endocrine and exocrine glands. 

The exocrine glands of the caddisfly Pycnopsyche scabripennis (Lim-nephilidae) secrete a defensive exudate which contains indole (138) and skatole (140) along with p-cresol (Table VIII). This secretion effectively repels invertebrate predators such as ants. 

The nervous system is divided into two parts the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS consists of the brain and spinal cord. The PNS consists of all afferent (sensory) neurons, which carry nerve impulses into the CNS from sensory end organs in peripheral tissues, and all efferent (motor) neurons, which carry nerve impulses from the CNS to effector cells in peripheral tissues. The peripheral efferent system is further divided into the somatic nervous system and the autonomic nervous system. The effector cells innervated by the somatic nervous system are skeletal muscle cells. The autonomic nervous system innervates three types of effector cells (1) smooth muscle, (2) cardiac muscle, and (3) exocrine glands. While the somatic nervous system can function on a reflex basis, voluntary control of skeletal muscle is of primary importance. In contrast, in the autonomic nervous system voluntary control can be exerted, but reflex control is paramount. 

The vesicles are intimately involved in the release of the transmitter into the synaptic or neuroeffector cleft in response to an action potential. Following release, the transmitter must diffuse to the effector cells, where it interacts with receptors on these cells to produce a response. The distance between the varicosities and the effector cells varies considerably from tissue to tissue. Smooth muscle, cardiac muscle, and exocrine gland cells do not contain morphologically specialized regions comparable to the end plate of skeletal muscle. 

The action of administered acetylcholine on effector systems innervated by parasympathetic postganglionic neurons (smooth muscle cells, cardiac muscle cells, and exocrine gland cells) resembled the actions produced by the naturally occurring plant alkaloid muscarine. The actions of both acetylcholine and muscarine on the visceral effectors are similar to those produced by parasympathetic nerve stimulation. Furthermore, the effects of acetylcholine, muscarine, and parasympathetic nerve stimulation on visceral effectors are antagonized by atropine, another plant alkaloid. 

Mechanism of Action An acetylcholine antagonist that inhibits the action of acetylcholine by competing with acetylcholine for common binding sites on muscarinic receptors, which are located on exocrine glands, cardiac and smooth-muscle ganglia, and intramural neurons. This action blocks all muscarinic effects. Therapeutic Effect Decreases GI motility and secretory activity, and GU muscle tone (ureter, bladder) produces ophthalmiccycloplegia, and mydriasis. 

Mechanism of Action Competitive inhibitors of the muscarinic actions of acetylcholine, acting at receptors located in exocrine glands, smooth and cardiac muscle, and intramural neurons. Composed of 3 main constituents atropine, scopolamine, and hyoscyamine. Scopolamine exerts greater effects on the CNS, eye, and secretory glands than the constituents atropine and hyoscyamine. Atropine exerts more activity on the heart, intestine, and bronchial muscle and exhibits a more prolonged duration of action compared to scopolamine. Hyoscyamine exerts similar actions to atropine but has more potent central and peripheral nervous system effects. TherapeuticEffect Peripheral anticholinergic and antispasmodic action, mild sedation. Pharmacokinetics None known... 

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