How can i draw the code outputs of simulated confidence intervals in matlab

Greeting

Could anyone help me in coding the following graphic overview of my problem. i have following TWO vectors suppose which are the output from a program simulated 4 times.

L=[2 3 4 5](lower limits of a CI) U=[6 7 8 9](upper limits of a CI)

Now i want to graph the values such that first value of L and first value of U should combine by line,second value of L combine with second value of U by line and so on.... Our x-axis has simulation number 1,2,3,and 4 whereas y-axix has value 2,4 ,6,8.In this way we have four vertical lines in two dimensional graph.Also i want a straight line parallel to x axis at y=4.

THANKING YOU ANTICIPATION