FIELDS H-I and H-2 



Columns 29, 30, 31, 



32, 33, and 34 



identified, with one of the 17- symbol series. In addition, if it is an isolated preparation, Field G 

 should be coded with Symbol R. 



When results of a test using a specific nerve-effector organ preparation are expressed only as 

 altering from normal the response of the organ to stimulation of the nerve (see Number 2 of the second 

 paragraph above), the coder can not arbitrarily assume that the effect is on any specific one of the 

 following: transmission of the impulse from nerve to effector, or on the effector organ, or on the nerve. 

 The coding pattern instead should state only what was demonstrated by the test- -the alteration, by the 

 test compound, of the normal action of the nerve on the organ. The correct entries in Fields T-2, H-l, 

 and T-l, are as follows: 



(I) Field T-2 : The organ's activity or state normally regulated or caused by the nerve is indi- 

 cated in Field T-2. For example, if the vagus-heart preparation is involved, Field T-2 is 

 used to indicate the cardiac process normally affected by the vagus nerve, heart rate. The 

 CBCC Code lacks a field for expressing the normal action of the nerve on the process or 

 state coded in Field T-2, just as the action of a secondary compound can not be expressed. 

 (Field T-l is used only to express the action of a test compound . ) In the present example, 

 Field T-2 can be coded to indicate only the action of the heart (cardiac rate, Symbol CI); 

 the action of the nerve on the heart action can only be, and must be, included in the 

 written abstract portion of Field T-2. (An alternative to this procedure would be the pro- 

 vision of many more special Field T-2 symbols such as "decreased cardiac rate due to 

 vagal inhibition", but it was believed this would represent an unnecessary complication 



to Field T-2. The other alternative would have been the provision of another coding field 

 for indicating action of nerves and secondary compound, but lack of space on the IBM card 

 decided against it. ) 



(II) Field H- 1 : The organ pair (nerve and effector) is coded in Field H-l. A special group of 

 such pairs are in Field H-l of the Code; when any experiment concerns a nerve and its 

 effector organ not in the Code, such a combination must be added to the Code and assigned 

 a symbol. (Note that if the test method provides for administration of the test compound 



so that only one member of the pair is exposed to the chemical, that nerve or effector 

 organ is coded in Field H-2, with the symbol for the pair coded in Field H-l. ) This entry 

 in Field H-l (any Field H symbol of the 17- series) lends a special interpretive significance 

 to the entry in Field T-2, in the same way that any entry in Field D lends a particular mean- 

 ing to Field T-2: any action (of the nerve or of the secondary compound) on the biological 

 state or process coded in Field T-2 is not indicated by coding but is only in the written 

 abstract of Field T-2. (See also the preceding paragraph on coding in Field T-2. ) 



(III) Field T- 1 : In Field T-l will be coded the action of the test compound on the action of the 

 negve , as the latter is recorded in Field T-2. This is accomplished by Symbol D, E, F, 

 or G of Field T-l. 



Example: The test compound reduces vagal slowing of the heart when the nerve 

 is stimulated (using an isolated vagus-heart preparation). 



Written in Field T-2: cardiac rate (retarded by normal vagal stimulation). 



9. Blood and its components (symbol series 33-), lymph (symbol series 35-), and reproductive 

 cells (Symbols 81C and 82B), included with gross structures of Field H 



Although most properly these structures are considered as tissue and cellular units of the 

 organism, they are included in Field H for reasons explained in Division 2 of the section on Specific 

 Directions and Explanations of Field I. 



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