Understanding Proton Pump Enzymatic Inhibitors — Transcript

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1. 0:02now that we generally know what the
2. 0:05enzymatic Inhibitors do and how they do
3. 0:08it we can apply that information to the
4. 0:10proton pump inhibitors
5. 0:13we said that the proton pump inhibitors
6. 0:15affected one of the enzymes in the
7. 0:19parietal cells
8. 0:21so where is the parietal cell if we go
9. 0:25all the way down into the stomach and we
10. 0:28took a microscopic view of the lining of
11. 0:32the stomach we would find that the
12. 0:34lining of the stomach has gastric pits
13. 0:37and we'd find in those gastric pits that
14. 0:41some of those cells were the parietal
15. 0:43cells
16. 0:45now the parietal cells as we said before
17. 0:48are the ones that secrete the hydrogen
18. 0:51ion or in other words the acid into the
19. 0:55Lumen of the stomach
20. 0:57recall that the parietal cell was the
21. 1:01same cell that we were affecting when we
22. 1:03were using the histamine II antagonist
23. 1:07or the histamine two blockers recall
24. 1:11that when there was stimulation from
25. 1:15gastrin and histamine and also
26. 1:19acetylcholine when all three of those
27. 1:21bound to their respective receptors on
28. 1:24the parietal cell then the hydrogen
29. 1:28potassium atpase pump could start
30. 1:31working
31. 1:32and recall that the histamine II
32. 1:35antagonists are competitive antagonists
33. 1:39they just compete with the histamine
34. 1:43that is also trying to bind to that same
35. 1:45receptor so the histamine II antagonists
36. 1:49decrease but don't totally eliminate the
37. 1:52production and release of the hydrogen
38. 1:55ions
39. 1:56now imagine if you could somehow totally
40. 1:59stop that pump stop the enzyme from
41. 2:03working
42. 2:04simplistically put that is what the
43. 2:07proton pump inhibitors do and as such
44. 2:10they're the most effective way that we
45. 2:13have to decrease stomach acid on the
46. 2:16long-term basis
47. 2:18in order to fully understand the proton
48. 2:21pump inhibitors we need to know a bit
49. 2:23more about the actual pump this is a
50. 2:26parietal cell that is in the gastric
51. 2:28pits of the stomach
52. 2:30the hydrogen potassium atpase pump that
53. 2:35were irreversibly inhibiting with the
54. 2:38proton pump inhibitors is a trans
55. 2:42membrane protein that means that it
56. 2:45spans the entire distance from the
57. 2:48inside of the cell to the outside of the
58. 2:51cell which is the portion that faces the
59. 2:55gastric pits
60. 2:57so why do we need a pump
61. 3:02a lot of substances cannot simply
62. 3:04diffuse from one side to another
63. 3:06sometimes you need an energy dependent
64. 3:09pump to get a substance from one side to
65. 3:11the other an example is the sodium
66. 3:14potassium atpase pump which is shown
67. 3:17right here
68. 3:18both sodium and potassium are small
69. 3:21particles but they have a charge they're
70. 3:24not neutral and as such they need an
71. 3:28energy dependent pump to travel from one
72. 3:31side to the other
73. 3:32this little video is depicting the
74. 3:35sodium potassium atps pump that's very
75. 3:38common throughout the entire system if
76. 3:41that pump stops for instance if we have
77. 3:44a lack of oxygen then the sodium winds
78. 3:47up in high concentrations inside the
79. 3:50cell and that osmotically pulls water
80. 3:53into the cell and the cell bursts
81. 3:57so you see if there was a toxin for
82. 3:59instance that irreversibly inhibited the
83. 4:02sodium potassium atps pump that would
84. 4:05result in death of the individual who
85. 4:08was affected
86. 4:10the hydrogen potassium atpase enzymatic
87. 4:14pump is similar to that sodium potassium
88. 4:17pump it's a very large enzymatic protein
89. 4:21that secretes hydrogen ions into the
90. 4:24Lumen of the stomach and when we take a
91. 4:27proton pump inhibitor we basically
92. 4:30inactivate that entire enzymatic protein
93. 4:34and that means that the medication needs
94. 4:37to degrade at the active site of the
95. 4:41enzyme over time or that the enzymes
96. 4:44need to be replaced before we get the
97. 4:48same level of acid back in the stomach
98. 4:50but unlike this sodium potassium atpase
99. 4:54pumps that are found throughout the body
100. 4:56the hydrogen potassium atps pump is not
101. 5:00necessary for our survival
102. 5:03we only have the hydrogen potassium pump
103. 5:06in two places in the body and the most
104. 5:09abundant place is in the parietal cells
105. 5:17I have a question for you about the
106. 5:20hydrogen potassium pump that is
107. 5:21irreversibly inhibited by Omeprazole and
108. 5:25other proton pump inhibitors just to
109. 5:27make sure that you have a really good
110. 5:29picture of that pump
111. 5:32which of the following is or are correct
112. 5:35the hydrogen potassium pump is a an
113. 5:39enzyme because it catalyzes or in other
114. 5:42words speeds up a reaction b a fairly
115. 5:46elaborate protein that is embedded in
116. 5:49the surface of the parietal cells in the
117. 5:51stomach
118. 5:53see A protein that acts as a pump
119. 5:56pumping out hydrogen ions into the Lumen
120. 5:59of the stomach or D all of the above
121. 6:05and you are correct if you answer D all
122. 6:07of the above are correct
123. 6:10Omeprazole and other proton pump
124. 6:12inhibitors are enzymes that act as
125. 6:15energy dependent pumps taking the
126. 6:18hydrogen ions from the inside of the
127. 6:21parietal cell and pumping that hydrogen
128. 6:23into the Lumen of the stomach
129. 6:26and you may be wondering what exactly
130. 6:28does the enzyme catalyze remember
131. 6:31enzymes catalyze reactions so what
132. 6:35reaction does it catalyze well it
133. 6:39catalyzes the reaction of taking an
134. 6:42energy molecule called ATP and turning
135. 6:46that into
136. 6:47ADP and from that reaction the protein
137. 6:51gets the energy that's necessary to run
138. 6:54the pump and so in other words the very
139. 6:58spot that is irreversibly inhibited by
140. 7:01Omeprazole and other proton pump
141. 7:03inhibitors basically blocks the energy
142. 7:06supply for the entire pump now that's an
143. 7:10effective medication