Acetophenone is also a component of castoreum, the exudate from the castor sacs of the mature beaver. In the late 19th and early 20th centuries, acetophenone was used in medicine. It was marketed as a hypnotic and anticonvulsant under brand name Hypnone. The typical dosage was 0.12 to 0.3 milliliters. It was considered to have superior sedative effects to both paraldehyde and chloral hydrate. In humans, acetophenone is metabolized to benzoic acid, carbonic acid, and acetone. Hippuric acid occurs as an indirect metabolite and its quantity in urine may be used to confirm acetophenone exposure, although other substances, like toluene, also
Ground substance as hyaluronic acid, heparan sulfate, dermatan sulfate, and chondroitin sulfate, proteoglycans which GAGs are bound to, and glycoproteins. Components of the ground substance are secreted by fibroblasts. Usually it is not visible on slides, because it is lost during staining in the preparation process. Link proteins such as vinculin, spectrin and actomyosin stabilize the proteoglycans and organize elastic fibers in the ECM. Changes in the density of ground substance can allow collagen fibers to form aberrant cross-links. Loose connective tissue is characterized by few fibers and cells, and a relatively large amount of ground substance. Dense connective tissue has a