Transcript Managing people in sport organisations: A strategic

Chapter 10
Companion site for Basic Medical Endocrinology, 4th Edition
Author: Dr. Goodman
FIGURE 10.1
Daily calcium balance in a typical adult.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.2
A thick ground section of the tibia illustrating cortical compact bone and the lattice of trabeculae of
cancellous bone. (From Fawcett, D.W. (1986) A Textbook of Histology, 11th ed., 201. Saunders,
Philadelphia.)
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.3
Cross-section through a bony trabecula. The pale blue area indicates mineralized matrix.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.4
Differentiation and activation of osteoclasts. c-Fms = receptor for macrophage colony stimulating
factor. M-CSF = macrophage colony stimulating factor. RANK = receptor activator of NF-kB.
RANKL = RANK ligand. OPG = osteoprotegerin. (Modified from Khosla, S. (2001) Minireview: The
OPG/RANKL/RANK system. Endocrinology 142: 5050–5055.)
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.5
Daily phosphorus balance in a typical adult.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.6
Drawing of a section through a human parathyroid gland showing small chief cells and larger
oxyphil cells. The cells are arranged in cords surrounded by loose connective tissue. (Modified from
Borysenko and Beringer. (1984) Functional Histology, 2nd ed., 316. Little, Brown, Boston.)
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.7
A. Posttranslational metabolism of PTH. The leader sequence (–31 to –6) is removed
cotranslationally in the endoplasmic reticulum. The hexapeptide –6 to 1 is removed in the Golgi
during packaging of the peptide. PTH 1-84 is the intact hormone. C terminal fragments are
generated in the secretory granules just prior to or during secretion. B. The known biologically
active portion of PTH, the epitopes required for detection and assay of the intact hormone.
Detection antibodies that recognize sequences downstream from the amino terminal tripeptide
cannot distinguish between the intact active hormone and its truncated antagonist.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.8
Effects of PTH on bone. PTH acts on cells of osteoblastic lineage to stimulate production of M-CSF
(macrophage colony stimulating factor) and RANKL (receptor activator of N-kappa B ligand), which
results in osteoclast formation and activation. Digestion of the bone matrix releases calcium and
phosphorus and growth factors that were deposited by osteoblasts when the matrix was laid down,
Growth factors stimulate osteoblast precursors to multiply, differentiate, and lay down new bone
matrix.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.9
Effects of PTH on the principal cells in the distal nephron. PTH stimulates insertion of epithelial
calcium channels in the luminal membrane and calcium extrusion mechanisms in the basolateral
membrane. GS = the stimulatory G protein; AC = adenylyl cyclase; cAMP = cyclic adenosine
monophosphate; PKA = protein kinase A.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.10
Effects of PTH on proximal tubule cells. Phosphorylation of NERF (sodium hydrogen exchange
regulatory factor) releases PT (sodium phosphate cotransporter) from anchoring sites in the
membrane. PTs migrate in the plane of the membrane to clathrin coated pits where they are
internalized and transferred to lysosomes and degraded. PTH also stimulates the expression and
activation of the enzyme (P450 1-hydroxylase) that converts 25-0HD3 to 1,25(OH)2D3, the active
form of vitamin D (see Figure 10.16). GS =  subunit of the stimulatory G protein; AC = adenylyl
cyclase; cAMP = cyclic adenosine monophosphate; PKA = protein kinase A; CREB = cyclic AMP
response element binding protein.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.11
Relation between plasma ionized calcium concentration and PTH secretion. (Redrawn and
modified from Brown, E.B. (1983) Four parameter model of the sigmoidal relationship between
parathyroid hormone release and extracellular calcium concentration in normal and abnormal
parathyroid tissue. J. Clin. Endocrinol. Metab. 56: 572–581.)
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Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.12
Regulation of PTH secretion. () = decrease; (+) = increase.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.13
Regulation of parathyroid hormone secretion by calcium (Ca2+). Heptihelical calcium receptors on
the surface of chief cells communicate with Ca2+ channels, adenylyl cyclase (AC), and
phospholipase C (PLC) by way of guanosine nucleotide binding proteins (Gi and Gq). The
resulting increase in Ca2+ and decrease in cyclic AMP (cAMP) concentration decreases protein
kinase A (PKA) mediated events that lead to secretion. IP3 = inositol trisphosphate. The increase in
calcium also accelerates cleavage of PTH to C-terminal fragments.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.14
Photomicrograph showing the relationship of calcitoninsecreting parafollicular cells to follicles in the
thryoid gland of a rat. Arrows point to parafollicular cells. The colloid-filled thyroid follicle is surround
by cuboidal epithelial cells. (Courtesy of Dr. John Cooke, Department of Cell Biology, University of
Massachusetts Medical School)
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.15
Alternate splicing of calcitonin/calcitonin gene related peptide (CGRP) mRNA gives rise to either
calcitonin or CGRP, with no shared sequences of amino acids.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.16
Biosynthesis of 1,25 dihydroxycholecalciferol (1,25(OH)2D3).
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.17
Effects of 1,25(OH)2D3 on intestinal transport of calcium. VDR = vitamin D receptor; ECaC =
epithelial calcium channels (also called TRPV5 and TRPV6); CaB =calbindin 9.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.18
Multiple negative feedback loops in the regulation of 1,25 dihydroxycholecalciferol synthesis. Solid
arrows indicate stimulation; dashed red arrows represent inhibition.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
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FIGURE 10.19
Overall regulation of calcium balance by PTH, calcitonin, and 1,25(OH)2D3. Solid green arrows
indicate stimulation; dashed arrows represent inhibition.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.20
Increased plasma calcium concentrations regulate calcium reabsorption in the thick ascending limb
of Henle’s loop. In this portion of the nephron calcium passes through the cellular junctions driven
by a positive luminal voltage. The calcium receptor signals through the guanosine nucleotide
binding protein Gq to activate PLC (phospholipase C) and form DAG (diacylglycerol), which
activates PKC (protein kinase C). Back diffusion of potassium through renal outer medullary
potassium channels (ROMK) is inhibited, which decreases the positive potential of luminal fluid and
limits reabsorption of sodium and chloride. The receptor also signals through Gi, thus inhibits
adenylyl cyclase (AC) reduces any cyclic AMP dependent stimulation of the sodium/potassium/2
chloride cotransporter. (PKA = protein kinase A)
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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FIGURE 10.21
Relation of estrogens to cytokines and growth factors in the overall economy of bones.
Companion site for Basic Medical Endocrinology, 4th Edition. by Dr. Goodman
Copyright © 2009 by Academic Press. All rights reserved.
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